INFORMATION & REQUIREMENTS ELECTRIC SERVICE - NStar

IMPORTANT INFORMATION FOR
BUILDERS AND CONTRACTORS
NEED POWER (New Construction Electric)
Includes installing new electric services, upgrading or moving a
service and temporary disconnection of a service
Phone . . . . . . . . . . . . . . . . . . . . . . . . . . . .888-633-3797
Fax: . . . . . . . . . . . . . . . . . . . . . . . . . . . . .781-441-8721
DIG SAFE . . . . . . . . . . . . . . . . . . . . . . . .888-344-7233
GENERAL CUSTOMER SERVICE
Residential Customers . . . . . . . . . . . . . . . . 800-592-2000
Business Customers . . . . . . . . . . . . . . . . . .800-340-9822
STREETLIGHT REPAIRS . . . . . . . . . . . . .800-785-4837
ENERGY EFFICIENCY
Residential . . . . . . . . . . . . . . . . . . . . . . . . .781-441-8720
Business . . . . . . . . . . . . . . . . . . . . . . . . . .781-441-8592
Cape Cod Only . . . . . . . . . . . . . . . . . . . . .800-797-6699
(Cape Light Compact)
CLAIMS - voice mail box . . . . . . . . . . . . .866-678-2792
THEFT OF SERVICE . . . . . . . . . . . . . . . .781-441-8537
www.nstar.com/business/builders_contractors
INFORMATION & REQUIREMENTS FOR ELECTRIC SERVICE
INFORMATION &
REQUIREMENTS
FOR
ELECTRIC SERVICE
CUSTOMERS
ELECTRICIANS
ARCHITECTS
ENGINEERS
BUILDERS
INSPECTORS
Revised 2009
Revised 2009

INTRODUCTION
At NSTAR Electric, we are committed to serving our customers
well, and providing them with safe, reliable electric service is one
of our most important priorities.This handbook, Information &
Requirements for Electric Service, was designed with that priority
in mind, and it contains the requirements within which safe
electric service can be supplied to our customers.
Inside you will find answers to many of the questions customers,
electricians, architects, engineers, builders, and inspectors
frequently ask related to electric service.You will also find there
have been a number of policy changes and other updates.We
encourage you to carefully review this new edition of Information
& Requirements for Electric Service.
We understand that a handbook cannot always take the place of
discussing a particular issue or question with someone.That is why
the NSTAR New Customer Connect Tech Center is staffed and
ready to respond to all of your power needs. Please call 888-
NEED-PWR (888-633-3797) Monday through Friday from 7:30
a.m. to 4:30 p.m. for a quick response to questions about new
construction, service upgrades, relocation, house moving or razing,
or information regarding other NSTAR services. NSTAR also has a
web site, www.nstar.com, which includes a host of topics for our
residential and business customers, as well as builders and
contractors. And because NSTAR regularly reviews this handbook,
any updates or changes can be found on our web site for your
convenience.
1

NSTAR ELECTRIC DISTRICTS
North District
South District
Cambridge District
Downtown Boston Network District
South District
Acushnet
Aquinnah
Barnstable
Bourne
Brewster
Carver
Chatham
Chilmark
Dartmouth
Dennis
Duxbury
Eastham
Edgartown
Fairhaven
Falmouth
Freetown
Harwich
Kingston
Lakeville
Marion
Marshfield
Mashpee
Mattapoisett
New Bedford
Oak Bluffs
Orleans
Pembroke
Plymouth
Plympton
Provincetown
Rochester
Sandwich
Scituate
(Humarock)
Tisbury
Truro
Wareham
Wellfleet
Westport
West Tisbury
Yarmouth
NSTAR ELECTRIC DISTRICTS
North District
Acton
Medway
Allston Millis
Arlington Milton
Ashland Natick
Bedford Needham
Bellingham Newton
Brighton Norfolk
Brookline Roslindale
Burlington Roxbury
Canton Sharon
Carlisle Sherborn
Chelsea Somerville
Dedham S. Boston
Dorchester Stoneham
Dover
Sudbury
East Boston Walpole
Framingham Waltham
Holliston Watertown
Hopkinton Wayland
Hyde Park Weston
Jamaica Plain West Roxbury
Lexington Westwood
Lincoln Winchester
Mattapan Woburn
Maynard
Medfield
2
Cambridge
District
Cambridge
Downtown
Boston Network
District
Back Bay
Boston
Charlestown
Fenway
South End
3

CHECKLIST
A CHECKLIST TO GUIDE YOU TO PROMPT AND
EFFICIENT SERVICE
Sometimes, even the most important pieces of the electric service
process may get overlooked. To help you determine if you’ve
covered all the bases when it comes to getting your electric service
energized, we have created the following checklist of items. Their
corresponding sections in this handbook also appear for more
detailed information.
• Work Order Application completed (form at
www.nstar.com)
• Outside location of meters (Article 704)
• Proper meter sockets in place (Article 715)
• Cold sequenced meters (Article 705)
• Two or more meters (Article 708)
• “Identification of Meter Sockets” form completed (Article 708)
• Are multi-sockets properly marked (Article 708)
• Does a clear cover plate exist for wired sockets pending
installation of a meter (Article 716)
• Correct service attachment hardware installed (Sketch 5)
• Fees paid (Article 206 & current fees available with the
Work Order Application form at www.nstar.com)
• Obtained wire inspector approval (Article 207)
TABLE OF CONTENTS
TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
NSTAR Electric Districts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Electric Service Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Contact Us . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Safety Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Frequently Asked Questions . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Utility Authorization Process . . . . . . . . . . . . . . . . . . . . . . . . . .17
Article 100 General Information . . . . . . . . . . . . . . . . . . . . . . . .18
101. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
102. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
103. Uniform Requirements . . . . . . . . . . . . . . . . . . . . . . . . .18
104. Effective Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
105. Enforcement of Rules . . . . . . . . . . . . . . . . . . . . . . . . . .19
106. Special Circumstances . . . . . . . . . . . . . . . . . . . . . . . . .20
107. Advisory Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
108. Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
109. Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
110. Diversion of Electrical Energy . . . . . . . . . . . . . . . . . . . .22
111. Cities and Towns Served; City/Town (Inspector of Wires
Information) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Article 200 Application for New or Additional Service . .29
201.Where to Apply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
202.When to Apply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
203. Availability of Service . . . . . . . . . . . . . . . . . . . . . . . . . .30
204. Additional Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
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TABLE OF CONTENTS
205. Relocation or Alteration of Service . . . . . . . . . . . . . . . .30
206. Customer Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
207. Inspection Certificates . . . . . . . . . . . . . . . . . . . . . . . . .31
208.Temporary Service and Installation Charges . . . . . . . . . . .31
209. Disconnecting and Reconnecting Overhead or
Underground Electric Services . . . . . . . . . . . . . . . . . . .32
210. Moving of Buildings or Structures . . . . . . . . . . . . . . . . .32
211. Company Liability . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
212. Resale of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Article 300 General Services . . . . . . . . . . . . . . . . . . . . . . . . .33
301. Availability of Service . . . . . . . . . . . . . . . . . . . . . . . . . .33
302. Number of Services . . . . . . . . . . . . . . . . . . . . . . . . . . .33
303. Service Characteristics . . . . . . . . . . . . . . . . . . . . . . . . .34
304. Customer Requirements . . . . . . . . . . . . . . . . . . . . . . . .37
305. Customer Generation . . . . . . . . . . . . . . . . . . . . . . . . . .37
306.Voltage Sensitive Equipment . . . . . . . . . . . . . . . . . . . . .40
307. Secondary Lightning Arresters . . . . . . . . . . . . . . . . . . . .40
308. Short Circuit Currents . . . . . . . . . . . . . . . . . . . . . . . . .40
309. Unbalanced Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Article 400 Installation of Services Policies,
Rights and Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
401. Public Grants and Special Permits . . . . . . . . . . . . . . . . .41
402. Private Property Permits and Crossing . . . . . . . . . . . . . .41
403. Extension of Lines In The Public Way . . . . . . . . . . . . . . .42
404. Ownership of Private Residential Overhead Construction . .44
405. Underground Service Credit . . . . . . . . . . . . . . . . . . . . .46
406.When Customers Install Their Own Electric Service Facilities .46
6
TABLE OF CONTENTS
407. Policy on Connections . . . . . . . . . . . . . . . . . . . . . . . .47
408.Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Overhead Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
409. Lines of Demarcation for Overhead Service . . . . . . . . . .48
410. Overhead Span Distances . . . . . . . . . . . . . . . . . . . . . .48
411. Point of Attachment . . . . . . . . . . . . . . . . . . . . . . . . . .48
412. Overhead Clearances . . . . . . . . . . . . . . . . . . . . . . . . .49
413. Overhead Secondary Services . . . . . . . . . . . . . . . . . . .49
414. Overhead Primary Service . . . . . . . . . . . . . . . . . . . . . .52
Underground Secondary Services . . . . . . . . . . . . . . . . . . .54
415. Lines of Demarcation . . . . . . . . . . . . . . . . . . . . . . . . .54
416. Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
417. Point of Attachment and Minimum Conductor Lengths . .54
418.Trench for Underground Service . . . . . . . . . . . . . . . . .55
419. Service Conduits on Private Property . . . . . . . . . . . . . .56
420. Conduit Installations - Minimum Specifications . . . . . . .56
421. Handholes or Manholes on Private Property . . . . . . . . .57
422. Underground Developments . . . . . . . . . . . . . . . . . . . .57
423. Underground Secondary Service from
NSTAR Overhead Line . . . . . . . . . . . . . . . . . . . . . . . .59
Underground Services from Underground
Distribution System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
424. Underground Secondary Services from Underground
Distribution System . . . . . . . . . . . . . . . . . . . . . . . . . .60
425. Installation of Underground Service When Construction is
Required on Private Property . . . . . . . . . . . . . . . . . . .61
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TABLE OF CONTENTS
426. Customer-Elected Installation of Underground Service on
Private Property . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
427. Underground Connections . . . . . . . . . . . . . . . . . . . . .61
428.Terminal Facilities/Terminal Boxes . . . . . . . . . . . . . . . .62
429. Grounding and Bonding . . . . . . . . . . . . . . . . . . . . . . .63
430. Pole-Mounted Transformers . . . . . . . . . . . . . . . . . . . .63
431. Mat and Fence Substation . . . . . . . . . . . . . . . . . . . . . .63
432. Padmount Transformer . . . . . . . . . . . . . . . . . . . . . . . .64
433. Building Vault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
Article 500 General Service Requirements . . . . . . . . . . . .68
501. Customer-Owned Equipment . . . . . . . . . . . . . . . . . . .68
502. Load Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
503. Separate Services . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
504. Size of Conduits and Conductors . . . . . . . . . . . . . . . . .69
505. Service Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . .69
506. Assigning Location of Service and Metering Equipment . .69
507. Unmetered Conductors . . . . . . . . . . . . . . . . . . . . . . .70
508. Metered Conductors . . . . . . . . . . . . . . . . . . . . . . . . .70
509. Overcurrent Protection of Feeders . . . . . . . . . . . . . . . .70
510. Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
511. Bonding Service Equipment: Secondary Services . . . . . .70
512.Temporary Service . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Article 600 Wiring and.Requirements . . . . . . . . . . . . . . . . .72
601. Signs and Automatically Controlled Lighting . . . . . . . . .72
602. Fluctuating Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
603. Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
TABLE OF CONTENTS
604. Insulating Transformers (sometimes referred to as isolating
transformers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
605. Power Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
606. Power Factor Correction Capacitors . . . . . . . . . . . . . . .74
607. Power Supply to Voltage Sensitive Equipment . . . . . . . .74
608. Power Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Article 700 Meters General Requirements . . . . . . . . . . . . .75
701. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
702. Meter Tampering . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
703. Standard Meter Installations . . . . . . . . . . . . . . . . . . . . .77
704. Meter Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
A. Outdoor Meters
B. Indoor Meters
705. Location of Service Disconnect and Current
Limiting Protection . . . . . . . . . . . . . . . . . . . . . . . . . .79
A. Hot Sequence
B. Cold Sequence
C. Current Limiting Protection
706. Meter Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
707. Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
708. Identification of Meter Sockets and Customer Disconnecting
Means for Multiple Meter Installations . . . . . . . . . . . . .81
709. Moving or Removing Metering Equipment . . . . . . . . . .82
710. Meter Connections . . . . . . . . . . . . . . . . . . . . . . . . . .82
711. Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
A. For Single Phase 3 wire, services
B. Meter Seals
8
9

TABLE OF CONTENTS
712. Meter Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . .84
A.Telephone Line for Interval Data Metering Applications
B. Optional Enhanced Metering Service
Meter Sockets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
715. Meter Sockets for Self-Contained Meters . . . . . . . . . . .84
A. Sockets with Manual Bypass
B. 200 Amperes or Less
C. 400 Amperes or Less (320 Amperes continuous Load Capacity)
D. Sockets for 200 Amperes or Less Residential or
Commercial Underground Services
716. Cover Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Instrument Transformer Installation . . . . . . . . . . . . . . . . .87
720. Instrument Transformers and Enclosures . . . . . . . . . . . .87
721. Use of Instrument Transformer Cabinets . . . . . . . . . . . .89
722. Pad-Mount Metering . . . . . . . . . . . . . . . . . . . . . . . . .89
723. Primary Metering . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Metal-Enclosed Bus Duct - 600 Volts or Less . . . . . . . . . . .91
730. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Metal-Enclosed Switchgear Over 600 Volts . . . . . . . . . . . .92
740. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
Article 800 Utilization Equipment . . . . . . . . . . . . . . . . . . .92
801. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
802. Nameplate Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
A. Definitions and Notes
B. Limitation of Motor Size
C. Single Phase Motors
D.Three phase Motors
E. Supply Voltage- Special
10
CONTACT US
803. Motor Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . .99
804. Fluctuating Loads . . . . . . . . . . . . . . . . . . . . . . . . . . .100
Article 900 Radio,Television, CATV & Carrier Installations . .101
901. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
902. Installation of Eliminator or Trap . . . . . . . . . . . . . . . .102
903. Service Quality Requirements . . . . . . . . . . . . . . . . . .102
904. Prohibition of Attachment to Poles . . . . . . . . . . . . . . .102
905. Clearance from Company Conductors . . . . . . . . . . . .102
906. Carrier Equipment . . . . . . . . . . . . . . . . . . . . . . . . . .102
907. Community Antenna Television (CATV) Systems . . . . .103
908. Cellular Telephone Towers . . . . . . . . . . . . . . . . . . . . .103
909.Town Owned Street Lights . . . . . . . . . . . . . . . . . . . .103
Appendix A Sketch Index and Sketches . . . . . . . . . . . . .104
Appendix B Massachusetts General Laws . . . . . . . . . . . .138
CONTACT US
During regular business hours (Monday thru Friday, 7:30 a.m. to
4:30 p.m.) please call 1-888-NEEDPWR (1-888-633-3797) to speak
with the NSTAR New Customer Connect Tech Center.
Mailing address:
NSTAR Electric
One NSTAR Way
Westwood, MA 02090-9230
Attention: NSTAR New Customer Connect Tech Center
You can also reach us online at www.nstar.com.
11

SAFETY REQUIREMENTS
SAFETY REQUIREMENTS
NSTAR has a number of requirements and tips to ensure your
safety. Please make sure to read the following safety requirement
highlights, and look for more throughout this booklet.
• The covering you may observe on some overhead
electrical wires is not insulation, so please do not touch it.
Any contact with our wires may cause serious injury or
death. Upon request, NSTAR will install line-hose guards
or erect other mechanical barriers to help protect against
contact with electrical lines. In some cases, customer
charges will apply for installation of line-hose guards.
• Heavy construction equipment such as cranes, derricks,
backhoes, dump trucks, etc. should not be operated closer
than 10 feet from energized power lines rated at 50 kV or
below. For lines rated over 50 kV, the minimum clearance
between the lines and any part of the equipment shall be
10 feet plus 0.4 inches for each kV over 50 kV as
prescribed by OSHA Regulations (S1926 subpart N-550-
(a) 15 (i) and (ii)).
• Massachusetts General Laws, Chapter 166, Sections 21A-
21G govern work in close proximity to high voltage lines.
NSTAR strongly recommends that a minimum clearance of
10 feet be maintained.
• Swimming pools should not be installed beneath overhead
facilities. Please contact NSTAR if you are planning to
install a pool near overhead or underground lines.You can
also check out the National and Massachusetts Electric
Codes for clearance information.
SAFETY REQUIREMENTS
• In general, antennas, banners, signs or similar customer
equipment shall not be attached to our poles except by
special permission from NSTAR. Such equipment when
installed nearby shall be far enough away so contact with
our facilities cannot take place during installation, removal,
or by accident. All clearances shall be as required by State
and National Safety Codes.
• To safeguard both your property and NSTAR, fuses or
breakers or those of branch circuits should only be
replaced with the proper size fuse or breakers for such
installation. Please contact NSTAR for additional
information.
• Consider adding ground fault interrupters to existing
circuits as prescribed by the Massachusetts Electrical Code.
12
13

FREQUENTLY ASKED QUESTIONS
FREQUENTLY ASKED QUESTIONS
1. Do I need an NSTAR authorization number before
work begins
Yes,You must obtain a utility authorization number before
NSTAR can perform any electric service work.
Please contact the NSTAR New Customer Connect Tech
Center at 888-NEED-PWR (1-888-633-3797) to get that
authorization number.
2. Do I need City/Town written approval for
installations
For all installations (new, upgraded, relocated or repaired), you
need to get written approval from what is called the “authority
having jurisdiction” before any service will be energized.This is
usually a state, city or federal authority, depending on the area.
3. Where do I install a meter socket
All meter sockets (commercial, industrial, and residential) are
installed outside at a pre-approved location that NSTAR and
the customer agree upon. At multi-meter locations, all meter
sockets must be properly marked with the floor and suite
number. NSTAR cannot energize installations that are
incorrectly marked, or not marked at all.
4. Where is a disconnect switch installed
Disconnect switches are located on the line side of the
individual meter socket (cold sequence metering) for the
following applications:
• On all ampere services on 480 volt three wire and
277/480 volt four wire installations
• For instrument transformer installations refer to article 720
FREQUENTLY ASKED QUESTIONS
Disconnect switches in all applications must be in close
proximity and within sight to each meter socket. Consult
NSTAR and the local inspection authority for specific
installation requirements.
5. Who performs permanent connections
On all service upgrades or replacement of damaged service
entrance cables, the electrician makes permanent connections
on all overhead services at the weather head and on all
underground services in the terminal box.
6. Who installs terminal boxes
The electrician installs all terminal boxes required for
underground services. If the service is energized, NSTAR will
disconnect and reconnect the service upon customer request.
Receipt of approval by the authority having jurisdiction will be
required before the service can be re-energized. Massachusetts
Electric Code governs the size of the terminal box.
7. Where is a customer’s weatherhead supposed to be
located
The customer’s weatherhead shall be located above NSTAR’s
point of attachment.
8. What type of conduit is required for service
installations
For a mast installation, a minimum size 2 inch rigid metal
conduit is required. Also, no other utility can be connected to
this conduit.
9. What connectors are required for copper to
aluminum connections
Bi-metal connectors are required on all copper to aluminum
connections.
14 15

FREQUENTLY ASKED QUESTIONS
10. At what height should the meter socket be mounted
The minimum meter height from the finished grade is three feet
to the center of the meter socket.The maximum height is six
feet to the center of the meter socket.
11. What material do I use for a riser pole section
Once you have approval from the authority having jurisdiction,
you can use minimum 3 inch schedule 80 PVC or rigid metal
conduit for a riser pipe section on the utility pole. Please note, if
rigid metal conduit is used a grounding bushing is required to be
installed with the wire lead connected to the system ground.
12. For Three phase, three wire installations what meter
socket should be used
For a three phase, three wire installation, a five-jaw meter
socket with an approved bar-type bypass is required.This socket
is designed to break A & C phases only. The fifth terminal must
be permanently attached to B phase at the six o’clock position.
13. When do I need a meter socket by-pass
A By-pass is currently required in all non-residential meter
sockets regardless of ampacity.
14. If I cannot meet one of the requirements in this
manual, what should I do
If you feel you cannot meet one or more of the requirements in
this handbook, you may request exemption. Requests for
exemptions should be formally submitted in writing to the
NSTAR New Customer Connect Tech Center. Please include:
• A reference to the specific requirement and corresponding
article number
• The exemption you need
• The reason for the exemption.
UTILITY AUTHORIZATION PROCESS
UTILITY AUTHORIZATION PROCESS
Early contact with the NSTAR New Customer Connect Tech
Center will assure that construction, service connections and
metering are performed within the requested in-service date.
Please be ready to provide complete customer name and service
address information, load and technical requirements to obtain the
necessary utility authorization number when requesting service.
If construction is required (i.e. a new service drop, new or
additional transformation, etc.), engineering designs are reviewed
and completed during this stage.
The service request will be approved by NSTAR’s engineering
group with any required rights and/or easements researched and
obtained.The NSTAR New Customer Connect Tech Center will
approve and collect any required customer charges.
To check the status of a work order during any stage in the utility
authorization process, please call the NSTAR New Customer
Connect Tech Center at 888-633-3797.
Receipt of approval by the authority having jurisdiction, (federal,
state, and/or city) in addition to any customer charges, releases a
utility authorization to the field for construction and the
installation of metering equipment. Approval can be in the form
of a City/Town wiring permit, or a letter of approval by the
appropriate federal or state inspectional authority.
16
17

ARTICLE 100-104
ARTICLE 100 GENERAL INFORMATION
101. Introduction
The Information and Requirements for Electric Service
booklet is issued to provide a thorough understanding between
NSTAR and its customers, architects, builders, electrical
contractors, consulting engineers and municipal inspectors. It
is also important to stay up to date on NSTAR’s Schedule of
Rates and its Terms and Conditions, as they are filed from time
to time with the Massachusetts Department of Public Utilities
(DPU) and which are subject to change.
102. Scope
The information contained in this booklet applies primarily to
electric service requirements for installations not exceeding
480 volts. Service requirements for installations at higher
voltages are subject to special negotiations with the NSTAR
New Customer Connect Tech Center.
103. Uniform Requirements
Many of NSTAR’s requirements are the same as those of other
electric utilities that serve cities and towns in adjoining
territories. However, differences in some requirements do
exist.To avoid misunderstanding, it is essential that a copy of
the local electric utility company’s requirements be obtained
and followed when work is to be done in its territory.
104. Effective Date
This issue of Information and Requirements for Electric
Service supersedes all previous issues for NSTAR Electric,
Boston Edison, COMElectric and Cambridge Electric and is
effective immediately for all new construction, with reasonable
allowance for the completion of work in progress or already
under contract. NSTAR reserves the right to revise, alter,
amend, add or repeal this information when necessary or
18
ARTICLE 105
appropriate and will endeavor to notify all interested persons.
It will be incumbent upon all interested persons to keep
themselves informed as to such revisions, alterations,
amendments, additions or repeals. NSTAR assumes no
responsibility to notify persons relative to such revisions,
alterations, amendments, additions or repeals.
105. Enforcement of Rules
All wiring intended for connection to the electrical conductors
of NSTAR shall be in accordance with requirements of the
authority having jurisdiction, the Massachusetts Electrical Code
and of NSTAR. Service connection to new customer wiring
installations will not be made until notice of approval of the
new wiring is received from the authority having jurisdiction.
All connections to NSTAR’s system shall be designed, installed
and operated in a manner that will not cause undue
disturbance to other customers, and will not restrict NSTAR
from maintaining proper system conditions. NSTAR reserves
the right to de-energize the service of any customer who, after
proper notice from NSTAR, continues to use any equipment or
apparatus that adversely affects the service of other customers
or any service that has not received approval from the
authority having jurisdiction.
In those instances where the electrician has not satisfactorily
fulfilled the requirements as stated in this manual, designated
employees of NSTAR will, upon receiving approval from the
customer, correct any omission or improper installation.
A charge for any services rendered will be forwarded to the
customer for payment.
In those instances where the electrician has not satisfactorily
fulfilled the requirement as stated in the Massachusetts
19

ARTICLE 106-108
Electrical Code, designated employees of NSTAR will, upon
receiving approval from both the authority having jurisdiction
and the customer, correct any omission or improper
installation. A notice of violation will be sent to the
electrician, the authority having jurisdiction and the customer.
A charge for any services rendered will be forwarded to the
customer for payment.
Any substantial changes shall be rectified by the electrician and
inspected by the authority having jurisdiction before any
service will be energized.
106. Special Circumstances
NSTAR reserves the right to waive these requirements in
special circumstances where conditions warrant. Any waiver of
these requirements will be in writing and will not be
considered as establishing a precedent nor be considered as
affecting NSTAR’s right to enforce any of the other
requirements as outlined in this manual.
107. Advisory Service
NSTAR will actively cooperate with architects, contractors and
engineers. However, neither by inspection nor by the rendering
of advisory service nor in any other way does NSTAR give any
warranty, expressed or implied, as to the adequacy, safety or
other characteristics of any equipment, wires, appliances or
devices owned, used or maintained by customers.
108. Rates
NSTAR furnishes its various services under tariffs and/or
contracts (“Schedule of Rates”) promulgated in accordance
with the provisions of M.G.L.c. 164, and MDPU decisions,
orders and regulations. Copies of Rate Schedules are available
upon request or from NSTAR’s website at www.nstar.com.
ARTICLE 109
NSTAR shall provide notice regarding its applicable rate
schedules annually to all customers. NSTAR shall advise each
new non-residential customer of the least expensive rate for
distribution service based on available information in NSTAR’s
existing records or as a result of a field inspection by NSTAR
when the customer provides information that is inconsistent
with NSTAR’s records. Upon receipt of adequate information
concerning rates, selection of the rate is the responsibility of
the customer. Each customer is responsible for accurately
describing his or her electrical needs and equipment and for
providing NSTAR with updated information as changes occur.
Each customer is entitled to change from one applicable
Distribution Service rate schedule to another upon written
application to NSTAR. Any customer who has changed from
one Distribution Service rate to another may not change again
within one (1) year or a longer period as specified in the tariff
under which the customer is receiving distribution service. A
change in rate that is requested by the customer will not
necessarily produce a retroactive billing adjustment.
109. Information
The NSTAR New Customer Connect Tech Center coordinates
all discussions with commercial, industrial, governmental and
residential customers regarding electric service.The NSTAR
New Customer Connect Tech Center shall provide information
regarding NSTAR service policy, rate application, service
request, status of service request, availability of service, service
requirements, and applicable service charges to all customers.
Please call 888-633-3797 for additional information.
20
21

ARTICLE 110-111
110. Diversion of Electrical Energy
A diversion of electrical energy is any method or device
used by any person that prevents an electric meter from
duly registering the quantity of electricity supplied by
NSTAR and/or any taking of any electrical current without
NSTAR’s consent.
Where there is evidence of meter tampering or theft of
electrical energy, such person or persons responsible shall
be liable for prosecution under penalty of Massachusetts
General Laws:
22
Chapter 164, Section 127 & 127A
Chapter 166, Section 38
Extracts from the above General Laws are printed
in this booklet in Appendix B.
111. Cities and Towns Served City/Town Inspector of
Wires Information
The following is a list of the cities and towns served by
NSTAR in which these requirements apply. Addresses and
telephone numbers of the city/town halls and the
appropriate inspector or wires telephone numbers have
been included for your convenience.
CITIES AND TOWNS SERVED
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
ACTON
472 Main Street
(978) 486-0167 (978) 486-0167
ACUSHNET 122 Main Street
(508) 998-0200 (508) 998-0025
AQUINNAH 65 State Road
(508) 645-2300 (508) 645-2300
ARLINGTON 730 Mass Avenue
(781) 316-3000 (781) 316-3393
ASHLAND 101 Main Street
(508) 881-0100 (508) 881-0117
BARNSTABLE 200 Main Street
(508) 862-4000 (508) 862-4089
BEDFORD 10 Mudge Way
(781) 275-1111 (781) 275-7446
BELLINGHAM 4 Mechanic Street
(508) 966-5800 (508) 657-2856
BOSTON
1 City Hall Plaza
(617) 635-4000 (617) 635-5300
BOURNE
24 Perry Avenue
(508) 759-0600 (508) 759-0615
BREWSTER 2198 Main Street
(508) 896-3701 (508) 896-3701 X127
BROOKLINE 333 Washington Street
(617) 730-2200 (617) 730-2110
BURLINGTON 29 Center Street
(781) 270-1615 (781) 270-1753
CAMBRIDGE 795 Mass Ave Fl 1
(617) 349-4000 (617)-349-6100
CANTON 801 Washington Street
(781) 821-5000 (781) 821-5003
23

CITIES AND TOWNS SERVED
CITIES AND TOWNS SERVED
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
CARLISLE 66 Westford Street
(978) 369-6155 (978) 369-6689
CARVER
108 Main Street
(508) 866-3400 (508) 866-3405
CHATHAM 549 Main Street
(508) 945-5160 (508) 945-5160
CHELSEA 500 Broadway
(617) 466-4000 (617) 466-4130
CHILMARK PO Box 119
(508) 645-2100 (508) 696-6400
DARTMOUTH 400 Slocum Rd.
(508) 910-1800 (508) 910-1889
DEDHAM 26 Bryant Street
(781) 751-9200 (781) 751-9180
DENNIS
485 Main Street
(508) 394-8300 (508) 760-6157
DOVER
5 Springdale Avenue
(508) 785-0032 (508) 785-0032 X245
DUXBURY 878 Tremont Street
(781) 934-1100 (781) 934-1100
EASTHAM 2500 State Highway
(508) 240-5900 (508) 240-5900 X233
EDGARTOWN 70 Main Street
(508) 627-6180 (508) 627-6115
FAIRHAVEN 40 Centre Street
(508) 979-4023 (508) 979-4019
FALMOUTH 59 Town Hall Square
(508) 548-7611 (508) 495-7473
FRAMINGHAM 150 Concord Street
(508) 532-5500 (508) 532-5520
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
FREETOWN PO Box 438 Assonet MA
(508) 644-2201 (508) 644-2202
HARWICH 732 Main Street
(508) 430-7513 (508) 430-7507
HOLLISTON 703 Washington Street
(508) 429-0608 (508) 429-0606
HOPKINTON 18 Main Street
(508) 497-9700 (508) 497-9745
KINGSTON 26 Evergreen Street
(781) 585-0500 (781) 585-0505
LAKEVILLE 346 Bedford Street
(508) 946-8800 (508) 947-6571
LEXINGTON 1625 Mass Avenue
(781) 862-0500 (781) 862-0500 X215
LINCOLN 16 Lincoln Road
(781) 259-2600 (781) 259-2613
MARION
2 Spring Street
(508) 748-3500 (508) 748-3516
MARSHFIELD 870 Moraine Street
9781) 834-5563 (781) 834-5555
MASHPEE 16 Great Neck Road
(508) 539-1400 (508) 539-1400
MATTAPOISETT PO Box 435
(508) 758-4100 (508) 758-4100
MAYNARD 195 Main Street
(978) 897-1001 (978) 897-8015
MEDFIELD 459 Main Street
(508) 359-8505 (508) 359-8505 X603
MEDWAY 155 Village Street
(508) 533-3200 (508) 533-3253
24 25

CITIES AND TOWNS SERVED
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
MILLIS
900 Main Street
(508) 376-7040 (508) 376-7044
MILTON
525 Canton Avenue
(617) 898-4878 (617) 898-4900
NATICK
13 East Central Street
(508) 647-6400 (508) 647-6450
NEEDHAM 1471 Highland Avenue
(781) 455-7500 (781) 455-7542 X210
NEW BEDFORD 133 William Street
(508) 979-1400 (508) 979-1470
NEWTON 1000 Commonwealth Ave.
(617) 796-1000 (617) 796-1075
NORFOLK One Liberty Lane
(508) 528-1408 (508) 528-5088
OAK BLUFFS PO Box 1327
(508) 693-3554 (508) 693-3554
ORLEANS 19 School Road
(508) 240-3700 (508) 240-3700 X343
PEMBROKE 100 Center Street
(781) 293-3844 (781) 293-3864
PLYMOUTH 11 Lincoln Street
(508) 747-1620 (508) 747-1620
PROVINCETOWN 260 Commercial Street
(508) 487-7000 (508) 487-7000 X520
ROCHESTER 1 Constitution Way
(508) 763-3871 (508) 763-5421
SANDWICH 130 Main Street
(508) 888-5144 (508) 888-4200
26
CITIES AND TOWNS SERVED
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
SCITUATE 600 Chief Justice
Cushing Highway
(781) 545-8741 (781) 545-8717
SHARON
90 South Main Street
(781) 784-1515 (781) 784-1525 X10
SHERBORN 19 Washington Street
(508) 651-7850 (508) 651-7850
SOMERVILLE 93 Highland Avenue
(617) 625-6600 (617) 625-6600 X5634
STONEHAM 35 Central Street
(781) 279-2600 (781) 279-2670
SUDBURY 288 Old Sudbury Road
(978) 443-8891 (978) 443-2209 X1362
TISBURY PO Box 1239
(508) 696-4200 (508) 696-4280
TRURO
24 Town Hall Road
(508) 349-7004 (508) 349-7004
WALPOLE 135 School Street
(508) 660-7289 (508) 660-7324
WALTHAM 610 Main Street
(781) 314-3000 (781) 314-3175
WAREHAM 54 Marion Road
(508) 291-3100 (508) 291-3100 X3193
WATERTOWN 149 Main Street
(617) 972-6465 (617) 972-6480
WAYLAND 41 Cochituate Road
(508) 358-7701 (508) 358-3605
WELLFLEET 300 Main Street
(508) 349-0300 (508) 349-0309
27

CITIES AND TOWNS SERVED
City/Town City/Town Hall Inspector of Wires
Address & Telephone Telephone
WESTON Town House Road
(781) 893-7320 (781) 893-7320 X319
WESTPORT 816 Main Road
(508) 636-1003 (508) 636-1035
WEST TISBURY PO Box 278
(508)-696-0102 (508) 696-0113
WESTWOOD 580 High Street
(781) 326-6450 (781) 320-1091
WINCHESTER 71 Mount Vernon Street
(781) 721-7133 (781) 721-7115
WOBURN 10 Common Street
(781) 932-4400 (781) 897-5846
YARMOUTH 1146 Rte 28
(508) 398-2231 (508) 398-2231 X261
28
ARTICLE 200 APPLICATION FOR NEW OR
ADDITIONAL SERVICE
ARTICLE 200-203
201. Where to Apply
Application for new service or the addition or alteration to an
existing service may be obtained by contacting the NSTAR
New Customer Connect Tech Center at 888-633-3797 or
online at www.nstar.com.
Upon completion of the application process, a utility
authorization number will be issued. This number shall be
referenced for any service request inquiry.
202. When to Apply
Application for any new service, temporary service, or the
addition or alteration to an existing service should be made
(preferably online or in writing) as far in advance as possible.
This is to allow time for engineering, ordering of material,
obtaining the necessary easement or grants of location, the
scheduling of public hearings by the appropriate governmental
agency, and scheduling and performing construction.Written
permission from the governmental agency or property owner
must be obtained by NSTAR before construction can begin. A
plot plan indicating the location of building(s) or addition(s)
and proposed service location should be included with new
electric load data.
An application may be submitted online at www.nstar.com in
the business section under Builders and Contractors. By mail,
for all districts, applications may be sent to:
NSTAR Electric
Attention: NSTAR New Customer Connect Tech Center
One NSTAR Way
Westwood, MA 02090-9230
29

ARTICLE 203-205
203. Availability of Service
Prior to ordering equipment or beginning any electrical wiring,
it is important that the customer contact NSTAR to determine
the availability of the type of service desired and if NSTAR has
additional requirements for such service. Location of the service
conductors, entrance and meter equipment, must be granted
before the building wiring is started.
NSTAR does not accept responsibility for information given
orally about the type of service available at specific locations.
This information must be confirmed in writing by an authorized
representative of NSTAR.
204. Additional Loads
NSTAR facilities are normally designed to meet customers’
initial requirements at the time the service is installed.When
additional load is contemplated, NSTAR must be notified in
writing as early as possible so that proper provisions can be
made to furnish the additional service.The customer must not
add additional load until notified by NSTAR in writing of the
conditions under which it can supply the increased load.The
customer will be held responsible for all damages caused by load
being added without notice to NSTAR.
205. Relocation or Alteration of Service
When relocation or alterations are to be made to an existing
service, NSTAR must be notified sufficiently in advance to
provide for the required change in service facilities and to
determine the conditions under which such changes will be
made. Any installation must conform to all requirements of
NSTAR, Massachusetts Electric Codes, and to the authority
having jurisdiction. Requests are processed in the order they
are received. In most cases, service relocations are made at the
customer’s expense.
30
ARTICLE 207-209
206. Customer Cost
Information relative to the customer’s portion of any service
construction costs will be provided by the NSTAR New
Customer Connect Tech Center. Payments are required prior
to the commencement of any construction by NSTAR.
Delaying of payment may adversely impact the construction
completion date originally established.
207. Inspection Certificates
NSTAR will not energize new, upgraded, relocated or repaired
wiring until approval has been issued by the authority having
jurisdiction. It is the responsibility of the customer or his
representative to follow whatever procedure is required by the
authority having jurisdiction so that NSTAR will receive the
approval prior to the time the wiring must be energized.
208. Temporary Service and Installation Charges
Temporary installations are made at the expense of the
customer. Flat charge quotes for standard service drop
installations may be obtained from the NSTAR New Customer
Connect Tech Center. For more complex temporary service
installations, design estimates are required and can be obtained
from the NSTAR New Customer Connect Tech Center. All
temporary services must be inspected by the authority having
jurisdiction. In all instances, early contact with NSTAR will
help to avoid unnecessary delays in receiving service.
31

ARTICLE 209-211
209. Disconnecting and Reconnecting Overhead or
Underground Electric Services
When disconnecting overhead and underground services,
contact the NSTAR New Customer Connect Tech Center for
applicable charges. There is no charge to disconnect and
reconnect a service if the customer is making the request for the
purpose of replacing an existing terminal box. NSTAR requires
advance notice to disconnect and reconnect a service at a
mutually agreed upon scheduled time. No service will be
reconnected until NSTAR receives approval from the authority
having jurisdiction.
210. Moving of Buildings or Structures
In order to accommodate house or building relocation, and
provided that NSTAR has received written notification of the
proposed route at least 30 days prior to moving, NSTAR at its
expense will disconnect or remove wiring along the route.
However, if NSTAR must remove or relocate poles or other
support structures along the route, this work will be performed
at the customer’s expense. Costs may be obtained from the
NSTAR New Customer Connect Tech Center. Municipal
permits and moving schedule allowances by each town or city
shall be the responsibility of the moving contractor along with
all coordination between affected authorities and utilities as to
route and work schedule to minimize inconvenience to
customers.
211. NSTAR Liability
NSTAR shall not be responsible for any failure to provide
electric distribution service nor for interruption, reversal or
abnormal voltage if such failure, interruption, reversal or
abnormal voltage is without willful default or gross negligence
on its part. Whenever the integrity of NSTAR’s system or the
32
ARTICLE 212-302
supply of electricity is threatened by conditions on its system
or on the systems with which it is directly or indirectly
interconnected, or whenever it is necessary or desirable to aid
in the restoration of service, NSTAR may, in its sole
judgment, curtail or interrupt electric distribution service or
reduce voltage to some or all of its customers and such
curtailment, interruption or reduction shall not constitute
willful default by NSTAR.
212. Resale of Energy
Electricity will not be delivered by NSTAR to any customer
of NSTAR for resale or redistribution by the customer or for
the use of others, without the prior approval of the
Massachusetts Department of Public Utilities (DPU).
ARTICLE 300 GENERAL SERVICES
301. Availability of Service
The type and/or size of service requested by a customer may
not be available at a given location. Please contact the NSTAR
New Customer Connect Tech Center for information
regarding availability of service prior to ordering new,
additional or replacement equipment. In some cases service
may be available only through special negotiation and at the
expense of the customer.
302. Number of Services
Only one alternating current service will be installed to a
building, except that two services may be installed to provide
single phase and three phase service.Two or more services
may also be installed at the option of NSTAR to provide
suitable capacity, to supply special loads or to meet unusual
conditions. Approval by the authority having jurisdiction will also
be required.
33

ARTICLE 303
Installations for customer convenience will be installed at the
customer’s expense. In any event, prior to ordering equipment
or starting a wiring installation involving both single phase and
three phase operation, the NSTAR New Customer Connect
Tech Center must be contacted regarding the characteristics of
the service to be supplied.Where electricity is delivered
through more than one meter, the cost of energy delivered
through each meter will be computed separately.
303. Service Characteristics
The following describes the characteristics and nominal
voltages of standard services, which are generally available.To
determine the type of service available at your location, please
contact the NSTAR New Customer Connect Tech Center. All
secondary voltage values stated herein are nominal, and are
subject to reasonable variations in accordance with the latest
revision of ANSI C84.
34
NOTE:
The Downtown Boston Network District as
mentioned in this book is defined as Boston proper, Back
Bay, portions of the South End and the Fenway. (See map at
front of book.)
For the North districts -formally Boston Edison
A. 120/240 volts, single phase, 3 wire, service & 240
volts, three phase, 3 wire, Delta service
Generally available outside the Downtown Boston
Network District. Single phase motors are limited to 5
horsepower or less.Three phase service is required for
motors exceeding 5 HP in size.The maximum combined
single-and three phase load to be served from NSTAR
facilities in the public way is limited to 150 kVa where
available. Customers requiring service beyond this limit
ARTICLE 303
must provide suitable private property facilities for necessary
transformation as coordinated by the NSTAR New
Customer Connect Tech Center.
B. 480 volts, three phase, 3 wire, Delta service
Generally available where the customer provides suitable
private property facilities for necessary transformation.
C. 120/280 volts, single phase, 3 wire, service
Normally available only in the Downtown Boston Network
District for connected loads not greater than 200 amperes.
This service may be available upon consultation with
NSTAR. Larger services must be three phase, 4 wire.
D. 120/208 volts, 3 phase, 4 wire,Wye service
Within the Downtown Boston Network District, some
locations requiring loads up to 300 kVa (800 amperes) of
transformer capacity may be supplied from NSTAR facilities
in the public way. In locations where transformer capacity in
the public way is not readily available, the customer will be
required to provide suitable private property facilities for
the supply transformers. For loads exceeding 300 kVa (800
amperes), the customer must provide suitable private
property facilities for the supply transformers as
coordinated by the NSTAR New Customer Connect Tech
Center.
Outside the Downtown Boston Network District, the
customer may be requested to provide suitable private
property facilities for necessary transformation.
E. 277/480 volts, three phase, 4 wire,Wye service
Generally available except that the customer must provide
suitable private property facilities for necessary
transformation. Minimum demand loads are a requisite,
typically 75 kVa or larger.
35

ARTICLE 303 ARTICLE 304-305
For the South and Cambridge Districts:
A. 120/240 volts, single phase, 3 wire, service
Most commonly used for residential customers and for
small commercial customers with up to 400 ampere
service entrance and with individual motors not over 5 HP.
Larger service entrances or larger motors may be accepted
with the specific approval of NSTAR. Customers requiring
service beyond this limit must provide suitable private
property facilities for necessary transformation as coordinated
by the NSTAR New Customer Connect Tech Center.
B. 120/208 volts, single phase, 3 wire, service
May be provided as the available single phase service when
the customer is located in a 120/208 volt, 4 wire, three phase
network or spot network area, upon consultation with NSTAR.
C. 120/208 volts, three phase, 4 wire,Wye service
Generally available except that the customer must provide
suitable private property facilities for necessary
transformation. Supplied to commercial and industrial
customers with loads larger than can be served by single
phase systems. This character of service is normally
restricted to loads of 500 kVa or less and not generally
available for service capacity in excess of 1600 amperes.
D. 277/480 volts, three phase, 4 wire,Wye service
Generally available except that the customer must provide
suitable private property facilities for necessary
transformation. Supplied to commercial and industrial
customers with loads of 75 kVa or larger.
For all of NSTAR:
Primary Voltage (15 kV or 25kV class)
Customers requesting primary service are required to
contact the NSTAR New Customer Connect Tech Center.
NSTAR’s approval must be obtained prior to purchase of
any material and equipment associated with the electric
service.
304. Customer Requirements
In certain instances, NSTAR will issue specific customer
engineering requirements.These requirements will be
furnished to customers or their representatives through the
NSTAR New Customer Connect Tech Center.To avoid
unnecessary expense and delay, the customer shall ascertain
these requirements prior to ordering equipment and/or
beginning construction.
Customers may be required to supply space for electrical
equipment on private property and may be required to furnish
and install non-electric facilities such as manholes, conduit,
transformer pads or enclosures, etc., in accordance with
specifications furnished by NSTAR and required by
Massachusetts Electric Code.
Customers will be required to provide an easement for any
NSTAR equipment located on the customer’s property. Initial
tree trimming may also be required at the customer’s expense.
305. Customer Generation
The following general requirements apply to customer
generating facilities designed to operate directly connected to
NSTAR’s electrical system (parallel operation–One that DOES
run in parallel with the NSTAR electrical grid) and those
which are designed to operate isolated from NSTAR’s system
36 37

ARTICLE 305 ARTICLE 305
(non-parallel operation–One that does NOT run in parallel
with the NSTAR grid). Requirements and specifications for
various types and sizes of customer facilities shall be obtained
from the NSTAR New Customer Connect Tech Center prior
to installation.
NOTE:
Parallel Operation Generators are NOT allowed in the
Network District (Downtown Boston, Cambridge and
New Bedford).
A. Emergency - Standby Generation (Non-Parallel
Operation)
Emergency (standby) generators are of the type that does
NOT operate in parallel with the NSTAR electrical grid.
The customer may install a standby generator to supply all
or part of the load in the event of a service interruption.
The customer’s wiring shall be arranged to prohibit the
interconnection of NSTAR’s service and the customer’s
alternate source of supply.This will require the installation
of a double-throw switch or its equivalent as approved by
NSTAR. (Sketch 1 illustrates some typical installations of
standby generating equipment)
NOTE:
Precautions must be taken where alternate means of
generation are employed, whether emergency or
otherwise, to eliminate the possibility of electrical
connection between NSTAR’s service and the customer’s
alternate source of supply (e.g., marinas with dockside
service, truck docks, etc.).The customer must notify the
NSTAR New Customer Connect Tech Center and provide
electrical details of generator installation and isolation
from NSTAR’s system.
B. Distributed Generation Systems
Are types of generators that do operate in parallel with the
NSTAR system. The more common types of distributed
generation include the following but does not constitute a
complete list:
• Photovoltaics (PV)
• Fuel Cells
• Wind Turbines
• IC Engine Cogeneration Systems
• Turbines
• Microturbines
Prior to the installation of any generator facilities, the
customer must notify the NSTAR New Customer Connect
Tech Center and it is necessary for all customers to fill out
and submit an interconnection application, regardless of the
size, prior to the installation of any distributed generation
systems. Interconnection applications as well as information
about the interconnection process for distributed generation
systems is available online at www.nstar.com. Customers
can also call the NSTAR Customer Connect Tech Center to
speak with an NSTAR representative about the
interconnection process. After the receipt of the
interconnection application, NSTAR takes the submitted
information and ensures that the proper utility
infrastructure is in place and that proper electrical
protections have been approved by NSTAR.
NOTE:
The application process is mandatory and is for the safety of
NSTAR personnel and the general public. It also ensures
that the customer’s installation will not affect the NSTAR
system electrical reliability.
38
39

ARTICLE 306-308
NSTAR is no longer in the generation business. Any
customer interested in selling electricity to NSTAR should
contact the NSTAR New Customer Connect Tech Center.
Further information regarding connecting distributed
generation to the NSTAR electrical grid can be found at
www.nstar.com.
306. Voltage Sensitive Equipment
Customers owning, or planning to purchase computers,
reproduction, X-ray, or data processing equipment or similar
devices should be aware that this type of equipment can be
extremely sensitive to power system transients or loss of
voltage. Customers should consult the manufacturer of their
equipment for suitable devices to protect against these
conditions. NSTAR cannot assume responsibility for voltage
variations that may be caused by switching, lightning surges,
motor vehicles hitting utility poles, or by other conditions
normal or emergency in nature.
307. Secondary Lightning Arresters
The customer may install secondary lightning protective
devices.The customer will be solely responsible for the
expense, installation, operation, maintenance and inspection of
such devices. Lightning arresters shall not be mounted on
meter sockets or metering equipment. Installation of lightning
protective devices shall be done in accordance with the
Massachusetts Electrical Code.
308. Short Circuit Currents
Available fault currents will vary with each residential,
commercial and industrial installation. It is the responsibility of
architects, engineers and wiring contractors to select the
proper service equipment to meet code requirements for short
circuit ratings. Inquiries concerning the magnitudes of available
fault currents for each particular location should be directed to
the NSTAR New Customer Connect Tech Center.
40
ARTICLE 309-402
309. Unbalanced Load
The customer shall at all times take and use energy in such a
manner that the load will normally be balanced to within 10
percent between phases on three phase services and between
live conductors on single phase services. NSTAR reserves the
right to require the customer to make necessary changes at the
customer’s expense to correct the unbalanced load conditions.
ARTICLE 400 INSTALLATION OF SERVICES
POLICIES, RIGHTS & PERMITS
401. Public Grants and Special Permits
Before poles, wire, or cables can be installed in, under, along,
and upon public ways and, in some cases, before they can be
run over or through public ways, NSTAR must obtain public
grants, state permits, and/or excavation or street opening
permits. In some cases special permits must also be obtained
from other companies maintaining facilities in such public
ways. These grants and permits can be issued in some
instances only after public hearings are held. Also, some
municipalities may observe certain periods of the year when
street opening permits are not granted. Under such
circumstances, delays in connecting service can be minimized
by applying for service at the earliest possible date.
Charges may be incurred by the customer when, at the
customer’s request, NSTAR facilities need to be relocated.
402. Private Property Permits and Crossing
Where it is required that a NSTAR-owned service be run
through or over private property not owned by the customer,
an easement, prepared by NSTAR, must be signed by the
owner of such property before service can be installed. It is the
customer’s responsibility to negotiate with the property owner
for said easement.
41

ARTICLE 403 ARTICLE 403
Where it is required that a Customer-owned service be run
over or through property not owned by the customer
requesting service, a service release, prepared by NSTAR, must
be signed by both parties. A copy signed by both customers
must be submitted to NSTAR before such service will be
energized.
403. Extension of Lines in the Public Way
A. Overhead Line Extensions for Residential,
Commercial & Industrial Customers within the
North District:
Requests for electric service requiring the extension of
NSTAR facilities in the public way will be subject to
analysis by the NSTAR New Customer Connect Tech
Center.They will determine whether or not the customer
shall underwrite, guarantee, or secure payment when the
delivery of service involves the use of NSTAR investment,
which, in the judgment of NSTAR, would not be offset by
the probable revenue obtained. Extension of NSTAR
facilities in the public way solely for the convenience of the
customer will be at the customer’s expense.
Installations of overhead services not requiring private
property construction will normally be installed without
charge, provided the point of attachment to the customer’s
building can be reached by one span of wire from NSTAR’s
nearest pole and that a right-of-way acceptable to NSTAR
can be obtained.When the delivery of service involves the
use of NSTAR investment, which in the judgment of
NSTAR, would not be offset by the estimated revenue to
be obtained, the customer shall underwrite, guarantee or
secure payment of minimum amounts.
Overhead secondary services requiring private property
42
construction from NSTAR underground lines will be
furnished, installed, owned and maintained by the customer.
It is the customer’s responsibility to assure that all
customer-owned equipment be tested and in working
order. During cases where NSTAR is required to operate
or install NSTAR-owned equipment into customer-owned
gear, the customer will be responsible for any repair or
replacement that is necessary due to failure of such
customer-owned equipment to operate properly.
B. Overhead Line Extensions for Residential
Customers within the Cambridge & South Districts:
It is NSTAR’s policy to install at no charge to the
customer, up to two wooden poles and three spans of wire,
along a public road or private way for a new service to a
single family dwelling. All construction along public or
private ways to service residential customers under this
policy will be performed by NSTAR or its agents.
When required to extend its single phase overhead
distribution lines, in excess of two poles, along a public or
private way to a residential home, NSTAR will provide an
overhead line extension in accordance with the provisions
of the line extension policy and agreement.
NSTAR will provide, install, own and maintain all facilities
including the overhead service drop from its facilities to a
residential home. Where it may also be necessary to install
pole(s) on private property to service the premises, please
refer to Article 404, Ownership of Private Residential
Overhead Construction.
Contact the NSTAR New Customer Connect Tech Center
for details of the Single Phase Residential Overhead Line
Extension Policy.
43

ARTICLE 404 ARTICLE 404
C. Overhead Line Extensions for Commercial &
Industrial Customers within the Cambridge &
South Districts:
Whenever NSTAR is required to extend its single phase or
three phase overhead distribution lines along a public way
or private way to serve a commercial or industrial
customer, the customer will provide a contribution-in-aidof-construction
for all costs of said overhead line extension
not supported by revenue.
Along public ways, and at the option of the customer on
private ways/property, all construction of an overhead line
extension for servicing commercial or industrial customers
will be done by NSTAR or its agent. NSTAR will own,
maintain and provide the line extension along the public
way and/or private ways including any tree trimming
where an easement has been provided.
NSTAR will also provide, own and maintain the overhead
service drop from its facilities to a commercial/industrial
customer.
Contact the NSTAR New Customer Connect Tech Center
for details of the Commercial/Industrial Line Extension
Policy.
404. Ownership of Private Residential Overhead
Construction
Where existing pole lines are owned and maintained by the
customer, the ownership and maintenance shall include, but
not be limited to, the replacement of defective or damaged
poles and fixtures, wires and the trimming of trees.
Maintenance construction performed by a contractor under
agreement with the customer shall conform to the
requirements of the local authority and standard specifications
44
for materials and methods as furnished by NSTAR. Such
construction is subject to approval by the authority having
jurisdiction.
For Cambridge & South Districts:
Additionally, in order to address the concern expressed by the
MDPU in its Hurricane Bob order DPU 91-228, regarding
private poles and subject to the following conditions, NSTAR
began a program to accept ownership of customer-owned
pole lines located on the customer’s property that were
constructed prior to November 1, 1994.
The requirements are:
A. The pole line to be owned by NSTAR must be connected
to an existing pole line owned by NSTAR.
B. The pole line to be owned by NSTAR must be readily
accessible by NSTAR’s vehicles via a driveway or roadway
to construct and maintain the line without special or
unusual permission or circumstances.
C. NSTAR is presented with legally valid easements,
provided at no cost to NSTAR with (A) rights to own and
maintain the pole line, including rights to trim trees as
normally required and (B) rights that allow NSTAR to
service other customers from the pole line, and to extend
the pole line to serve other customers.
D. The customer must pay to NSTAR the tax liability
associated with the facilities to be acquired.
The poles must meet these conditional guidelines:
A. The pole must have more than 10 years of life left (based
on a 30 year life expectancy), must be in good condition
(i.e. no woodpecker holes, no ground or shell rot).
45

ARTICLE 405-406
46
B. Poles must meet minimum NSTAR standards for pole size
for the application.
C. Cross arms must have more than 10 years of life left.
Contact the NSTAR New Customer Connect Tech Center
for details.
405. Underground Service Credit
For Cambridge and South Districts only:
For residential customers requesting installation of an
underground service at customer’s expense, a credit may be
available to the customer. The credit is based on the cost
NSTAR would normally incur to install up to two poles on
private property to service a new single family dwelling.
Contact the NSTAR New Customer Connect Tech Center for
details of this policy.
406. When Customers Install Their Own Electric
Service Facilities
In certain instances, the customer may be allowed or required
to employ a contractor to install on private property all or a
portion of the necessary service construction under the
following conditions:
A. All material and construction shall conform to NSTAR
standards.
B. Only authorized NSTAR personnel are permitted to make
any type of new electrical connection to NSTAR supply
lines or equipment.
C. Before the installation will be energized, authorized
NSTAR representatives will inspect the installation for
conformance to NSTAR construction standards.
D. Prior to energizing the line, the customer must submit a
copy of the “as built plans” and easements shall be
ARTICLE 407
conveyed to NSTAR. In addition, the customer will be
responsible for the tax liability on such construction.
Please contact the NSTAR New Customer Connect Tech Center
before beginning construction.
407. Policy on Connections
NSTAR will connect customer’s wiring to NSTAR facilities for
final connections for permanent or temporary services and will
not permit or tolerate unauthorized persons to connect to
NSTAR conductors or equipment.
NSTAR will allow licensed electricians to cut and reconnect
single services for service upgrades at the customer's weather
head or underground services in the customer's terminal box
provided the steps listed below are observed:
A. Contact the NSTAR New Customer Connect Tech Center to
have the existing meter unlocked. Allow five working days.
B. Notify the local inspection authority of the proposed work
and obtain all necessary permits. No reconnection is
permitted without prior approval of the local inspection
authority. See Article 111 for information regarding your
local inspection authority.
C. The added load on the service shall not be utilized until
NSTAR has completed all of its work.
D. All conductors must be cut and reconnected on the
customer’s side of the existing connections. Proper
connectors shall be used and three feet of extra conductor
must be supplied to form a drip loop.
E. The old meter should be used whenever possible to make
the connection in the new socket. If jumpers are necessary,
permission to install jumpers must be obtained from the
NSTAR New Customer Connect Tech Center.
47

ARTICLE 408-411 ARTICLE 412-413
408. Violations
When any of the requirements of this book are not followed,
NSTAR will send a notice of violation to the electrician, with a
copy forwarded to the authority having jurisdiction. If any
damage occurs or metering equipment is lost as a result of the
actions or lack of actions by the electrician, appropriate
restitution may be sought.
OVERHEAD SERVICES
409. Lines of Demarcation for Overhead Services
All construction on the customer’s premises beyond the point
of attachment (normally, the anchor bolt) is a part of the
private wiring system, which is furnished, installed, owned and
maintained by the customer, with the exception of such
metering equipment furnished by NSTAR. (See Sketch 2)
410. Overhead Span Distances
The maximum single-span distance NSTAR will run its
overhead residential service drop conductors to the point of
attachment for 100-200 amp service entrance is approximately
125 feet. Building heights, large conductors, the necessity for
street, driveway, sidewalk crossings and other possible factors
may reduce the maximum permissible spans. Contact the
NSTAR New Customer Connect Tech Center for details on
service entrances larger than 200 amperes.
411. Point of Attachment
The service drop shall be attached to the building or other
structure at a suitable point, determined and approved by
NSTAR, which is not less than 12 feet nor more than 25 feet
above the finished grade level. (See exceptions and details on
Sketch 3).
48
The service drop shall be accessible from a ladder placed on a
solid surface at ground level and shall meet the minimum
clearance requirements specified by Article 412.The
customer/contractor shall furnish and install suitable service
support hardware. Refer to Sketches 4 and 5 for details of
hardware installations. Contact the NSTAR New Customer
Connect Tech Center for details on service entrances larger
than 200 amperes.
412. Overhead Clearances
Clearance requirements for overhead service conductors are
set forth in section 23 of the National Electrical Safety Code
and Articles 230-9, 230-24, and 680-8 of the National
Electrical Code and the Massachusetts Electrical Code.
Sketch 3 graphically depicts NSTAR’s minimum allowable
clearance standards, some of which exceed the abovereferenced
codes. Interpretation of the codes, questions
concerning Sketch 3, or inquiries as to other clearance
requirements should be directed to the NSTAR New
Customer Connect Tech Center.
413. Overhead Secondary Services
Overhead secondary services from the public way are
restricted to installations where the service is 400 amperes or
less single phase, 3 wire or three phase, 3 wire. All other loads
and voltages require transformation on private property. See
Article 414, Overhead Primary Services.
Upon completion of the customer’s wiring work, on all new
services, NSTAR will make the final connection between the
customer’s service and NSTAR’s distribution system.The
customer shall furnish all connections larger than 500 KCMIL.
For further details see Article 407, Policy on Connections.
49

ARTICLE 413 ARTICLE 413
50
For the North District:
The first section of wire, not to exceed 125 feet, shall be
furnished, installed, owned, and maintained by NSTAR from the
pole line in the public way. All other private property
construction will be furnished, installed, owned and maintained
by NSTAR at the customer’s expense, subject to the following
requirements:
A. NSTAR is granted written permission from the property
owner to install such poles, conductors, apparatus and
attachments as required to provide electric service on
private property.
B. If the public pole line is on the opposite side of the street,
NSTAR, at its own expense, will furnish, install, own and
maintain the first pole on private property.
C. The customer shall make provisions to guarantee NSTAR
access to the private property facilities for installation and
maintenance.These provisions will include plowing, paving,
or whatever is necessary to ensure safe passage for NSTAR
vehicles and personnel.
D. When the customer has installed the private property
construction, ownership will be transferred to NSTAR.
Refer to Article 406,When Customers Install Their Own
Electric Facilities.
E. Any extension of private property construction required to
provide service to another building on the same property,
will be subject to the above requirements and will be at
customer’s expense.
F. Any extension of private property construction required to
provide service to another customer will require an
easement from the private property owner.
For the South & Cambridge Districts – Residential
Overhead Services from Overhead Lines:
Where a NSTAR-owned distribution line exists along a public
or private way, it is the general policy of NSTAR, subject to
review in each case, to install at NSTAR’s expense, up to two
wooden service poles and three spans of overhead wires and
appurtenances on the customer’s property to serve a single
family dwelling. Any additional construction that may be
required will be at the customer’s expense.The customer will
pay to NSTAR the carrying charge on the cost of construction
in excess of the first two poles and three spans of wire. NSTAR
will bring residential overhead electric service to the nearest
point of attachment on the house or building by the most
direct practical route as determined by NSTAR.
Where a NSTAR-owned distribution line does not exist and a
line extension along a public or private way is necessary to
serve the customer, the cost of the private property
construction will be at the customer’s expense. Please refer to
the Residential Overhead Line Extension Policy or contact the
NSTAR New Customer Connect Tech Center.All construction
will be owned and maintained by NSTAR.
NSTAR ownership of any poles on private property is effective
only upon receipt of adequate legal protection as to property
rights, trimming rights, and rights to extend the pole line to
serve others, with associated documents to be approved by
NSTAR counsel. Legally valid easements at no cost to NSTAR
will be required whenever NSTAR-owned poles are located on
private property.
Under the Residential Overhead Line Extension Policy, the
customer may elect to install an equivalent system approved by
NSTAR but shall transfer said system to NSTAR for all of the
51

ARTICLE 414 ARTICLE 414
above purposes, at no cost to NSTAR.The customer will pay
NSTAR the carrying charge on poles and lines in excess of the
first two poles and three spans of wire.
414. Overhead Primary Services -
Cambridge & South Districts:
A. Overhead Primary Service for Residential Real Estate
Developments:
A developer or customer may request NSTAR to
construct an overhead line extension to serve a residential
real estate development. NSTAR will provide, own and
maintain all facilities including the overhead service drop
as each dwelling in the development is prepared to receive
such service. Note: Some towns have bylaws that require
all new developments to have underground utilities.
The customer may elect to construct an overhead line
extension per NSTAR’s specifications and shall transfer
such facilities to NSTAR for ownership and maintenance
prior to energizing.The customer or developer will pay
NSTAR the tax liability associated with NSTAR acquiring
these facilities.
Contact the NSTAR New Customer Connect Tech Center
for details of the Overhead Line Extension Policy for
Residential Real Estate Developments.
B. Overhead Primary Service to Commercial &
Industrial Customers:
The customer may request NSTAR to construct an
overhead line extension to provide service for commercial
or industrial customers on a tract development or parcel
of land.The customer will provide a contribution-in-aidof-construction
for all costs of said overhead line extension
not supported by revenue, per company policy.
The customer may elect to construct an overhead line
extension per NSTAR’s specifications and transfer such
facilities to NSTAR for ownership and maintenance prior
to energizing.The customer will pay NSTAR the tax
liability associated with NSTAR acquiring these facilities.
Commercial and Industrial customers shall contact the
NSTAR New Customer Connect Tech Center whenever an
overhead line extension is required to serve a premise.
For the North District:
Residential, commercial and industrial customers whose total
load exceeds the limits as outlined in Article 413 and Article
416 may be required to provide space on private property for
NSTAR-owned transformers and protective equipment.
NSTAR makes the final decision for the type and nature of the
service.
All construction by the customer on private property must be
performed in accordance with NSTAR standards and will be
inspected by a NSTAR representative for approval before
service will be energized. Please contact the NSTAR New
Customer Connect Tech Center for details. (See Sketch 10)
Please contact the NSTAR New Customer Connect Tech
Center for information regarding this policy in the South and
Cambridge Districts.
52 53

ARTICLE 415-417
UNDERGROUND SECONDARY SERVICES
415. Lines of Demarcation
On underground secondary services, all private property
construction beyond the first point of attachment is a part of
the private wiring system, which is furnished, installed, owned
and maintained by the customer, with the exception of such
metering equipment furnished by NSTAR.
416. Size
Underground secondary services from the public way are
restricted to installations where the total required demand load is:
54
A. For radial, the maximum combined single and three phase
load to be served from NSTAR facilities in the public way
is limited to 150 kVa or less where available. In the South
districts the single phase services are limited to 75 kVa
demand. Radial service is normally supplied outside the
Downtown Boston Network District.
B. For Downtown Boston Network, New Bedford Network
or Cambridge Network service in the secondary network
service area (which only includes services 300 kVa or less,
three phase, 4 wire, 120/208 volts) where available. All
other loads and voltages require transformation on private
property.
417. Point of Attachment & Minimum Conductor Lengths
For all new installations NSTAR will make the connection to
the first point of attachment to the customer’s wiring
system. In urban districts, a minimum length of 24 inches for
each service entrance conductor shall be left at the terminal
box; at handholes, sufficient cable to extend across the
handhole and at least 3 feet above the top of the handhole
opening is required to provide for connection to NSTAR
ARTICLE 418
service conductors. If the service entrance conductors are
350 MCM or larger, the minimum length of each conductor
shall be 3 feet from connections in terminal box. The final
connections are the exclusive responsibility of NSTAR.
In areas where padmount transformers are provided, a
minimum length of 3 feet at handholes and 7 feet at padmount
transformers shall be left to provide final connections to
NSTAR facilities. The contractor shall leave the coil in the open
trench outside NSTAR facilities or as coordinated with NSTAR.
NSTAR shall make all final connections.
Upon completion of the customer’s wiring work, on all new or
replaced services, NSTAR will make the final connection
between the customer’s service and NSTAR’s distribution
system.The customer shall furnish the following connectors:
A. All aluminum connections.
B. Copper connectors larger than 500 KCMIL.
Contact the NSTAR New Customer Connect Tech Center for
details.
418. Trench for Underground Service
The trench for underground secondary service shall be deep
enough to permit service conductors to be installed not less
than 30 inches below finished grade or as required by the
authority having jurisdiction. The trench bed shall have a
uniform pitch and be free of large stones. Rock foundations
shall be covered with 3 inches of fine compacted fill.When
backfilling, the first 6 inches shall be fine fill and hand tamped.
Large stones shall be removed from the final fill, which may be
tamped with power tampers. All digging will be the customer’s
responsibility, and shall be subject to inspection by a NSTAR
representative prior to backfilling.
55

ARTICLE 419-420 ARTICLE 421-422
56
Underground service conductors on private property for
electric service, not in excess of 600 volts, shall be minimally
sized for 100 amp service and shall meet the Massachusetts
Electrical Code standards.
Underground secondary services shall have a separation of at
least 12 inches from water and gas systems. Underground
secondary services may be installed with telephone conductors
and in the same trench with water, gas or similar systems,
provided the clearances are maintained (refer to the
Massachusetts Electrical Code).
419. Service Conduits on Private Property
All service conduits installed on private property by the
customer shall be constructed in accordance with NSTAR’s
specifications. Plans shall be submitted to NSTAR for approval
prior to installation. Underground service conduits shall have a
smooth interior, free from all burrs or sharp edges. Special care
must be given the installation on non-metallic conduits.
Information regarding approved types of conduits will be
furnished upon request by the NSTAR New Customer Connect
Tech Center.
420. Conduit Installations-Minimum Specifications
Service conduits in urban underground systems shall not be
smaller than 4 inch nominal pipe size. Unless otherwise
approved, all service conduits shall be schedule 40 PVC.
Service conduits shall be limited to lengths of 250 feet by the
installation of suitable handholes as specified by NSTAR.
Long sweep bends shall be required for change in direction of
any conduit section.
The bends in any conduit section, including those in the street,
shall not total more than 180 degrees and such bends shall be
made at a radius of not less than 20 inches. Any unusual
bends, grades or conductor sizes shall be approved by NSTAR
before proceeding with construction. Please contact the
NSTAR Tech Center.
Service conduit joints shall be made secure so that the sections
will not be thrown out of line by the shifting ground. Metallic
conduits may be joined by threaded couplings. Other types of
couplings for metallic or non-metallic conduits shall be
approved by NSTAR. Please contact the NSTAR New
Customer Connect Tech Center.
Service conduit shall be installed not less than 30 inches below
finished grade, and where possible shall be installed to drain to
the nearest handhole or manhole. The end of the conduit
within a building shall be securely sealed around the outside of
the conduit.
Underground services may be installed in the same trench
with telephone, water, and gas or similar services, provided the
clearances specified in the preceding paragraph are maintained.
421. Handholes or Manholes on Private Property
Handholes on private property, used as points of demarcation,
are owned and maintained by NSTAR. All other handholes on
private property are owned and maintained by the customer.
All manholes/conduits on private property are owned and
maintained by the customer.
422. Underground Developments
Underground distribution systems, such as shopping centers,
industrial parks, underground commercial development
(UCD), underground residential developments (URD), etc.
may be subject to special negotiations requiring a written
57

ARTICLE 422 ARTICLE 423
agreement. Contact the NSTAR New Customer Connect Tech
Center for details on the electric line extension policies.
Developers interested in an underground distribution system in
a commercial project should contact the NSTAR New
Customer Connect Tech Center at least one (1) year before the
desired service date.
Developers in the South district should refer to the following manuals:
Underground Distribution System Specification 4-0385 (UDS)
and Commercial Underground Distribution System
Specification 1-0796 (CUDS) for more details.
Residential:
A developer may apply for an underground line extension to
service a residential real estate development. Upon
completion of the installation, all non-electric facilities
installed by the customer in the future public way will be
transferred to NSTAR for ownership and maintenance. In
certain cases in the South districts where the customer installs
conduit on private property to be used for primary cable and
that conduit will always be accessible to NSTAR crews,
ownership of that conduit will also be transferred to NSTAR.
Transfer of ownership is subject to inspections and/or tests as
required and approved by NSTAR.
In the South districts, the developer may construct an
underground line extension, including the electric facilities per
NSTAR specifications using an NSTAR approved contractor
and transfer these facilities to NSTAR for ownership and
maintenance. The underground service cable from the
customer’s property line to the service entrance shall be
owned and maintained by the customer.
Commercial:
The developer shall install, own and maintain all underground
non-electric facilities and secondary service systems at the
developer’s expense.
NSTAR will install, own and maintain the primary cable and
transformers, when such facilities are required or in the South
districts the developer may construct an underground line
extension per NSTAR specifications and transfer the primary
cable system to NSTAR for ownership and maintenance.
Transfer of ownership is subject to inspections and/or tests as
required and approved by NSTAR.
423. Underground Secondary Service from NSTAR
Overhead Lines
The entire expense of supplying the underground service
conductors from the point of termination on the pole to the
customer’s building or structure, including installation of a
handhole at the property line, shall be borne by the customer.
The customer shall own and maintain the underground service
from the property line or handhole to the building. NSTAR
will assume ownership and maintenance responsibility from the
pole to the handhole for residential services. NSTAR will make
the final connections to its facilities after approval is received
from the authority having jurisdiction for the customer-owned
portion of the service. Some services will require a junction
box. Contact the NSTAR New Customer Connect Tech Center
for additional details. (See Sketches 6A and 6B)
When more than one underground service is anticipated,
NSTAR will provide the oversized wire to be installed from the
handhole to the pole. Contact the NSTAR New Customer
Connect Tech Center for additional details.
58
59

ARTICLE 424
60
Electrical contractors and customers will be responsible for
any damage associated with work that they perform in the
public way. Any related installations (e.g. handhole) will
become the property of NSTAR at the time the line is
energized. Access to these installations must be provided to
NSTAR personnel for continued operation and maintenance by
NSTAR. A warranty must be provided to NSTAR that all of the
materials and workmanship meet NSTAR’s specifications and
shall be free from defects for a period of five years from the
date the line is ready to be energized.
UNDERGROUND SERVICES FROM UNDERGROUND
DISTRIBUTION SYSTEM
424. Underground Secondary Services From
Underground Distribution System
In areas where NSTAR maintains an underground distribution
system, service will be furnished, installed, owned and
maintained by NSTAR, provided the total length of service
conduit and cable on private property is not in excess of two
feet. (See Sketch 8) This work shall not include cutting through
or restoration of the foundation, floors or partitions.The
customer must core drill or sleeve thru the foundation wall to
connect 1-4 inch pvc per 400 amp of switch size (for example
an 800 amp switch requires 2-4 inch sleeves thru the
foundation wall). The terminal box shall be furnished and
installed by the customer. See Article 428,Terminal Facilities /
Terminal Boxes.When a new building is being constructed, an
opening shall be provided through the foundation wall suitable
for the conduit entrance.
If additional service conduit and cable are required on private
property to complete the service installation, they shall be
installed in accordance with NSTAR procedures in this manual.
ARTICLE 425-427
425. Installation of Underground Service When
Construction Is Required On Private Property
NSTAR will install at its own expense such service up to a
point two feet inside the property line if the estimated revenue
to NSTAR offsets the cost. Before proceeding with the work,
the customer shall consult the NSTAR New Customer Connect
Tech Center as to the location of the service conduit at the
property line. Beyond that point, the customer may elect to
have NSTAR install the service conductors at the customer’s
expense up to the customer’s first handhole, manhole or
terminal box or the first point of attachment on private
property.The customer may elect to perform this work under
conditions outlined in the following section.
426. Customer-Elected Installation of Underground
Service on Private Property
Before proceeding with the work, the customer shall consult
NSTAR as to the location of the service conduit at the property
line.The customer shall install a handhole that complies with
the Massachusetts Electrical Code or a manhole 2 feet inside
the property line, at the location of NSTAR’s service conduit,
to provide means for connection to NSTAR’s cable.The
connection in the private property manhole will be made by
NSTAR at the customer’s expense. Service conduit and cable
required beyond this manhole to the customer’s building shall
be installed by the customer.
427. Underground Connections
Upon completion of the customer’s service work and approval
of the authority having jurisdiction, NSTAR shall make the final
connection between the customer’s cable and NSTAR’s
distribution system on all new services. At least 24 inches of
each service entrance conductor shall be left extending into the
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ARTICLE 428
terminal box to provide for connection to NSTAR service
conductors.Where the service entrance conductors are 350
KCMIL or larger, the minimum length for each conductor shall
be 3 feet.
428. Terminal Facilities / Terminal Boxes
Under all circumstances, terminal facilities shall be furnished,
installed, owned and maintained by the customer. All terminal
boxes shall be provided with a means for padlocking by
NSTAR.The locking mechanism shall consist of two (2)
locking hasps located on opposite sides of the terminal box. For
services rated at 800-1000 amperes, see Sketch 9 for additional
requirements. All terminal boxes shall be in accordance with
the Massachusetts Electric Code.When an existing terminal
box is to be replaced by the customer, NSTAR will, at
customer request, de-energize the service at no cost. Upon
completion of this replacement, and when approval has been
received by the authority having jurisdiction, NSTAR will reenergize
the service.
Special Facilities:
On installations requiring more than two service cables per
phase, a special terminal facility may be required, especially in
the Downtown Boston Network District of Boston.These
installations, generally 800 amps and above, require the use of
limiters as protective devices.The terminal facility is to be
furnished, installed, owned and maintained by the customer
under all circumstances. All special terminal facilities will be
provided with a means for padlocking by NSTAR. Line-side
connections will be made by NSTAR. All installations of this
type will be coordinated through the NSTAR New Customer
Connect Tech Center. See Sketch 9 for details. Installations
greater than 1000 amps will require a limiter frame cabinet per
ARTICLE 429-431
NSTAR standards and must be coordinated through the
NSTAR New Customer Connect Tech Center to arrange a site
meeting with NSTAR Meter Operations. In addition, the
customer must core drill or sleeve thru the foundation wall to
connect 1-4 inch pvc per 400 amp of switch size (for example,
an 800 amp switch requires 2-4 inch sleeves thru the
foundation wall).
429. Grounding and Bonding
All secondary alternating current services having a grounded
neutral shall have that neutral grounded on the customer’s
premises at the service equipment as required by the
Massachusetts Electrical Code.
CUSTOMER REQUIREMENTS FOR PRIVATE
PROPERTY INSTALLATIONS:
430. Pole-Mounted Transformers
Overhead services from a pole-mounted transformer on
private property are restricted to installations where the
required transformer capacity is 75 kVa or less for single
phase, or 150 kVa or less for three phase. For installations
exceeding the above values, a padmounted transformer is
required.
431. Mat and Fence Substation
This type of private property installation is no longer available
for new customers. It will be the responsibility of the existing
customer to maintain the concrete transformer mat, liquid
retaining curb where required by the authorities having
jurisdiction, buried ground grid, stone fill, fence, and cable
structure(s). Each of these items must meet NSTAR standards,
which are available from the NSTAR New Customer Connect
Tech Center.
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63

ARTICLE 432
432. Padmount Transformer
This type of private property installation is available in both
overhead and underground distribution areas. Size and location
of the padmount transformer and secondary transclosure cabinet
(where required) will be designated or approved by NSTAR.
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General Requirements: The customer shall provide,
own and maintain the following:
A. In the South districts, a precast concrete transformer pad,
buried ground grid, all conduit and stone fill or liquid curb
where required by the authorities having jurisdiction. In
the North districts, the customer may install a precast pad
or pour a pad in place for three phase transformer
installations. For single phase installations, NSTAR will
supply a fiberglass pad for installation by the customer.
B. Installation of multiple secondary cables and conduits must
be coordinated through the NSTAR New Customer
Connect Tech Center prior to the pouring of concrete for
the pad.When an installation requires more than 8 sets of
secondary conduits with conductor sizes up to 750 KCMIL
copper or aluminum, a secondary cable transclosure
cabinet must be provided and installed by the customer.
The Company will install secondary cables into the
transclosure to connect to the customer installed cables.
This cabinet must be located a minimum of 10 feet from
the transformer.
C. NSTAR-approved protective guards, such as concrete-filled
pipe, in areas where the transformer is subject to vehicular
damage. Additional protection may be required for the
padmount location (i.e., fences, barriers, etc.) by the
authorities having jurisdiction. Padmounted equipment
shall not be enclosed or obstructed by plantings, walls, etc.
ARTICLE 432
Minimum clearances for all NSTAR districts shall be ten
feet to the front and four feet to the remaining three sides.
(See Sketches 10 and 11)
D. All secondary cable.
E. The customer shall furnish all approved secondary
connectors. Additional installation equipment may also be
required. NSTAR will make final connections at the
transformer secondary terminals.
Additional detailed standards and requirements for the
South district are located in:
1. Specification 4-0385, revised August 1998,
Underground Distribution System (UDS)
2. Specification I-0796, revised May 1998 Commercial
Underground Distribution System (CUDS)
3. Sketch 10 Required Clearances Around NSTAR Owned
Facilities
4. Sketch 11 Padmounted Transformer protection from
Vehicular Traffic
F. Overhead Area – Riser Pole On Public Way:
The primary riser conduit, cable and the underground
construction to a point 2 feet inside the property line will
be furnished and installed by NSTAR at customer expense.
A NSTAR-approved bonded contractor may install conduit
and cable in the public way, provided NSTAR obtains the
necessary rights. Contact the NSTAR New Customer
Connect Tech Center for more information.
For the North District:
The customer shall pay the cost of furnishing and installing
all primary cable beyond the 2-foot line to the padmount
transformer. NSTAR shall maintain that portion on private
property at customer expense.
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ARTICLE 432
66
For the South and Cambridge Districts:
The customer may pay the cost of furnishing and installing
all primary cable up to the padmount transformer. NSTAR
will own and maintain the primary cable and transformer.
For all of NSTAR:
All other construction on private property including the
terminal box, if any, will be installed, owned and
maintained by the customer.
If NSTAR is required to change the location of the pole on
which an underground service originates, the necessary
charges to the underground service shall be at the
customer’s expense.
G. Overhead Area: Riser Pole On Private Property
The primary conduit from the transformer pad to the riser
pole, including the riser on the pole, will be furnished,
installed (NSTAR’s specifications), owned and maintained
by the customer.The primary cable from the transformer
pad to the riser pole will be furnished, installed and
maintained by NSTAR at customer expense.
H. Underground Area:
For the North District:
The primary conduit from the transformer pad to a point
two feet inside the customer’s property line at a point
designated by NSTAR will be furnished, installed, owned,
and maintained by the customer. NSTAR will extend this
conduit to the underground system. NSTAR will install the
first section of the primary cable from the street manhole
to the padmount transformer on private property and
charge the customer for furnishing and installing the
primary cable beyond 2 feet inside the property line. NSTAR
will maintain this portion of the cable at customer expense.
ARTICLE 432-433
For the South and Cambridge Districts:
The customer will install the primary conduit from the
transformer pad to NSTAR’s distribution facility. NSTAR
will install the first section of the primary cable from the
street manhole to the padmount transformer on private
property and may charge the customer for furnishing and
installing the primary cable beyond 2 feet inside the
property line. Contact the NSTAR New Customer
Connect Tech Center to determine ownership and
maintenance of this portion of the installation.
433. Building Vault
This type of private property installation is available in both
overhead and underground distribution areas in the North
District, excluding the Downtown Boston Network District
(for customer vaults in the Downtown Boston Network
District please contact the NSTAR New Customer Connect
Tech Center). A building vault is required when no space is
available outside the building for a padmount transformer.The
customer shall:
A. Provide vault space within the building large enough to
accommodate NSTAR’s transformer(s) and protective
equipment in an area free from moisture and other
contaminants.Where possible, the vault should be located
on outside walls and have an outside entrance door for
easy access.The vault size, grounding, ventilation,
drainage, access and location must be approved by NSTAR
and the authority having jurisdiction, and be in accordance
with Massachusetts Electric Code.
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ARTICLE 501-503
B. Provide 24-hour access, lighting, convenience and phasing
outlets, grounding systems, heat detection system, drainage
and ventilation as required by NSTAR.
C. Supply and install all secondary bus or conduit and cable to
the vault. Final connection of the customer’s secondary
conductors to the secondary terminals of the transformers
will be made by NSTAR.
ARTICLE 500 GENERAL SERVICE REQUIREMENTS
501. Customer-Owned Equipment
It is the customer’s responsibility to assure that all customer
owned equipment is tested and in working order. In situations
where NSTAR is required to operate or attach to customer
owned equipment, the customer will be responsible for any
damages caused by the operating failure of such customer
owned equipment.
502. Load Balance
The customer’s wiring system shall be arranged in order to give
the best possible load balance on the service. Severely
unbalanced customer loads that affect the stability of the
distribution system will be disconnected until the customer
makes the necessary improvements to eliminate the imbalance.
503. Separate Services
Separate service entrances, conduits, and cables are required
for each type of service.
Only one service may be connected to one Overhead service run.
Any new or upgraded overhead service feeding a single building
with multiple meters shall be limited to one service cable or
conduit with one weatherhead. With a required service
upgrade, there shall remain one weatherhead with the service
cable being upgraded.
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ARTICLE 504-506
504. Size of Conduits and Conductors
Conduit and conductor sizes shall be in accordance with the
Massachusetts Electrical Code.
505. Service Equipment
One or more service switches or circuit breakers will be
furnished, installed and maintained by the customer as part of
the permit for wiring for each service entrance. These devices
shall conform to the following:
A. All service switches or circuit breakers shall be of a type
approved by a qualified testing laboratory, by NSTAR, and
by the authority having jurisdiction.
B. All service equipment located on the line side of meters
must be of the enclosed type, with facilities for locking by
NSTAR. Fuse replacement or circuit breaker reset by the
customer must be possible without disturbing the
enclosure lock.
C. Where multiple service equipment is provided, each
disconnecting means shall be marked in a conspicuous,
legible and permanent manner to indicate which portion
of the installation it controls.
506. Assigning Location of Service & Metering Equipment
The locations of service and metering equipment are
designated by NSTAR and are subject to the approval of the
authority having jurisdiction. This approval must be obtained
before wiring begins. Contractors must notify NSTAR of their
intent to do work at least two weeks in advance to allow time
to assign locations. The point of service attachment should not
be less than 12 feet nor more than 25 feet above the final grade
level. For further clarification refer to Sketches 2, 3,6A and 6B.
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ARTICLE 507-511 ARTICLE 512
507. Unmetered Conductors
Unmetered conductors shall not be installed in the same
raceway with metered conductors. When unmetered
conductors are installed through private basements or other
private areas not containing NSTAR equipment, they shall be
enclosed in a continuous length of exposed rigid raceways or
conduit as required by Massachusetts Electric Code. The
installation of pull boxes, fittings or other similar devices is not
permitted in such areas. In a block of stores, the unmetered
conductors shall be enclosed in a rigid metal raceway or
encased in concrete with the approval of the authority having
jurisdiction.
508. Metered Conductors
Metered conductors from two or more meters shall not be
grouped in one raceway or distribution panel, except by
written permission from NSTAR and as required by
Massachusetts Electric Code.
509. Overcurrent Protection of Feeders
Proper overcurrent protection of feeders shall be required by
the Massachusetts Electrical Code.
510. Fuses
NSTAR does not maintain a stock of fuses for customer-owned
equipment. The contractor or customer shall supply and install
all fuses. On installations where special types of fuses are used
in service equipment, such as high interrupting capacity or
current limiting fuses, it is very important that the customer
maintain a replacement stock of required fuses.
customer’s premises at the service equipment. The systemgrounding
conductor shall be connected to the neutral
conductor. The system-grounding conductor shall provide an
effective ground as required by the Massachusetts Electrical Code.
Three phase, 3 wire Delta connected services shall not be
grounded.
Mobile Homes: Grounding and bonding of mobile homes is a
special case covered by the Massachusetts Electrical Code.
512. Temporary Service
A service will be considered a “temporary service” unless
permanent service entrance equipment is installed. Unless
otherwise approved by NSTAR in writing, temporary service
shall be defined as any installation intended for removal upon
completion of the job.
The customer shall provide a service entrance which meets the
requirements of a permanent installation with respect to
service drop clearances, metering, grounding and safety.The
service entrance may be installed on a pole set 3 feet or more
in the ground or on a guyed or braced timber structure that
meets the specifications and installation requirements of
NSTAR.Where a 6 inch x 6 inch upright is to be assembled
using three 2 inch x 6 inch planks, these planks should be
bolted together at intervals not exceeding 4 feet. Installation of
such temporary service is subject to the approval of the
authority having jurisdiction. Refer to Article 208 for
installation charges. (See Sketch 12)
511. Bonding Service Equipment
Secondary Services: All secondary services having a grounded
neutral shall have that neutral adequately grounded on the
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71

ARTICLE 601-604
ARTICLE 600 WIRING AND VOLTAGE
REQUIREMENTS
601. Signs and Automatically Controlled Lighting
Signs and automatically controlled lighting loads shall be wired 3
wire. Flashing signs shall be properly balanced throughout each
portion of the flashing cycle.NSTAR shall be contacted in
advance when signs or automatically controlled lighting are to
be installed.
602. Fluctuating Loads
Loads such as electric welders, furnaces, boilers, compressors,
pumps, molding machines or similar equipment with load
fluctuations shall not be installed, except under conditions
specified by NSTAR. Please contact the NSTAR New
Customer Connect Tech Center to advise of the proposed
installation of this equipment.Voltage dips caused by load
fluctuations, regardless of their frequency, must not cause
undue disturbance to other customers nor hinder the Company
in maintaining proper voltage conditions. For customers served
by a dedicated transformer on single phase lines, welders
should conform to NEMA-EEI Standards and not draw more
than 46 amperes at 240 volts. (Please see more specific details
in Article 804)
603. Grounding
All secondary services having a grounded neutral shall have that
neutral adequately grounded on the customer’s premises at the
service equipment as required by the Massachusetts Electric Code.
604. Insulating Transformers (sometimes referred to as
isolating transformers)
Where lighting or other reduced voltage equipment from three
phase, 3 wire, Delta service is permitted by NSTAR, insulating
72
ARTICLE 605
transformers having ANSI approved primary and secondary
windings are required.The secondaries of these insulating
transformers will be properly grounded and balanced in
accordance with the Massachusetts Electrical Code.The
minimum number of single phase transformers that may be
used to serve the reduced voltage load on a three phase, 3
wire, service is shown in the table below:
The minimum number of single phase transformers
that may be used to serve the reduced voltage load
on a three phase, 3 wire, service
Reduced Voltage Load in
Kilowatts or % of Total
Demand on Service
(whichever is Larger)
Minimum
Number
Transformers
Less than 5 1
5 to 10 inclusive 2
More than 10 3
NSTAR should be contacted prior to buying insulating
transformers for this type of installation.
605. Power Factor
Maintenance of high power factor is of the utmost importance
to both the customer and NSTAR in the operation of their
distribution systems. Power factors of 90 percent or higher are
advantageous for both the customer and NSTAR.The NSTAR
New Customer Connect Tech Center should be contacted in
advance regarding any installation likely to develop power factors
of less than 90 percent.
The Commonwealth of Massachusetts has addressed the issue of
power factor in Massachusetts State Building Code, 780 CMR,
73

ARTICLE 606-607 ARTICLE 608-701
as amended. Section 1312.2 Power Factor: Utilization
equipment greater than 1,000 watts and lighting equipment
greater than 15 watts with an inductive reactive load
component shall have a power factor of not less than 85
percent under rated load conditions. Power factor of less than
85 percent shall be corrected to at least 90 percent under rated
load conditions. Power factor corrective devices, installed to
comply with this code, shall be switched with the utilization
equipment, except where this results in an unsafe condition or
interferes with the intended operation of the equipment.
606. Power Factor Correction Capacitors
When the customer desires to install capacitors for the
purpose of power factor correction, the capacitors must be
installed to prohibit inadvertent reverse current flow at low
loads to NSTAR’s system.They must also be sized and installed
in such a manner as not to create harmonic interference on
NSTAR’s lines.The NSTAR New Customer Connect Tech
Center must be contacted prior to the ordering and installation
of such equipment. NSTAR will de-energize any service that
creates voltage distortion or inadvertent current flow to its
system.
607. Power Supply to Voltage Sensitive Equipment
Customers who install computers, X-ray equipment,
emergency devices or other voltage sensitive equipment are
advised that auxiliary devices and relays must be employed to
filter out voltage spikes and to adjust for voltage variations.
NSTAR is not responsible for voltage variations that may be
caused by switching, lightning surges, motor vehicles hitting
utility poles or by other conditions beyond NSTAR’s control.
608. Power Quality
NSTAR delivers high quality power.The increased use of
customer-owned equipment that can adversely affect the
quality of electric service to other customers is of great
concern. In order to maintain delivery of high quality power to
all of our customers, the installation of customer-owned
equipment that may affect NSTAR’s electric system, shall meet
NSTAR specifications. NSTAR reserves the right to withhold
or disconnect service where installation of such loads or
equipment is detrimental to NSTAR’s service to other
customers. For further information please contact the NSTAR
New Customer Connect Tech Center.
NSTAR has adopted IEEE Std. 519-1992, IEEE Recommended
Practices and Requirements for Harmonic Control in Electric
Power Systems. However, NSTAR reserves the right to enforce
stricter guidelines than those outlined in IEEE 519-1992, when
in NSTAR’s opinion, the harmonic contributions from a
customer or group of customers contributes to a degradation
in the quality of service to other customers on the system to an
unacceptable level. NSTAR may require corrective actions be
taken at the customer’s expense.
ARTICLE 700 METERS & GENERAL REQUIREMENTS
701. General
All energy supplied by NSTAR shall, in general, be measured
by appropriate meters for billing purposes. The installation of
meters and metering equipment shall comply with the
requirements set forth in this Article.
Meters will be provided, maintained, installed, moved, and
removed only by authorized NSTAR employees. No changes in
metering equipment of any nature whatsoever are to be
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75

ARTICLE 702 ARTICLE 703-704
undertaken by any other persons except when special
permission is first obtained from the NSTAR Meter
Operations Department via the NSTAR New Customer
Connect Tech Center. Meter boards, meter banks, sockets,
and protective enclosures, where required, are to be
furnished and installed by the customer or the customer’s
electrical contractor.
It is the Customer’s responsibility to assure that all customerowned
equipment is tested and in working order.
For cases where NSTAR is required to operate or install
NSTAR-owned equipment into customer owned equipment,
the customer will be responsible for any repair or
replacement that is necessary due to failure of such customerowned
equipment.
Where, in the judgment of NSTAR, a meter installation may
be subject to damage, the customer will be required to
provide a NSTAR-approved enclosure or other protective
device for the meter equipment or relocate the equipment at
the customer’s expense.
702. Meter Tampering – Warning
Do not tamper with meter, instrument transformers, or
other metering devices or NSTAR wiring under penalty of law.
Massachusetts law provides penalties for tampering with the
meters or equipment of an electric utility. See Massachusetts
General Laws, Chapter 164, Section 127 and Section 127A.
NSTAR Revenue Assurance is responsible for the
investigation of theft and unmetered electricity and all such
information should be reported. The NSTAR Revenue
Assurance Hotline number is 781-441-8537 and is available
for anonymous calls regarding theft or unmetered service.
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703. Standard Meter Installations
The Meter Technical Department will specify the type and
location of metering for each installation. Please contact the
Meter Operations Department via the NSTAR New Customer
Connect Tech Center for additional information. In general the
following is standard:
A. Self-contained single phase socket metering where the
service capacity is 400 amperes or less.
B. Self-contained polyphase socket metering where the
service capacity is 400 amperes or less.
C. Instrument transformer installation for all installations
where the service capacity is more than 400 amperes.
All exceptions from NSTAR’s standard meter installations
must be approved by NSTAR.
All class 320 ampere self contained meter installations shall be
pre-approved by the local inspection authority prior to
starting work.
Refer to section 705 for location of service disconnect.
The secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum and
shall not exceed 75 feet.
704. Meter Locations
Outdoor meter locations are required for all new, rebuilt,
relocated or extended (residential and commercial)
installations. Exceptions to this requirement will be
permitted only with specific prior approval of
NSTAR. Each location shall be readily accessible to NSTAR
representatives for meter reading, testing, and maintenance.
Service will not be provided if reaching the meter requires
77

ARTICLE 704 ARTICLE 705
NSTAR employees to use adjacent property, climb fences or
other obstructions, or cause damage to the customer’s
shrubbery or flower beds in gaining access to the meter.
In areas subject to vandalism or damage, permission may be
granted for indoor meters. All such indoor meters shall be in
a readily accessible location next to the service entrance
equipment.
In multiple occupancy buildings, for residential or
commercial use, permission may be granted for
meters to be installed indoors in one common
location accessible to all occupants.
Metering equipment shall not be installed in locations subject
to excessive moisture, dust, heat, chemical fumes or in
locations which are hazardous or inaccessible.
Meter locations are not permitted in living spaces, stairways
or under stairways, display windows, attics, boiler rooms,
elevator shafts; over doors, stoves or sinks; directly under, in
the rear of, or close to, steam, gas, water or drain pipes or
near moving machinery.
In special circumstances, meter locations may be required to
be changed to ensure the integrity of the metering equipment.
A. Outdoor Meters
Outdoor meter sockets should be mounted so that the
face of the meter is less than 6 feet above the final grade.
In no instance will any meter be installed with the center
of the meter more than 6 feet, nor the center of the
meter less than 3 feet above the final grade. A clear area
of 3 feet is required in front of each meter.(See Sketch 13)
Installation On Poles
NSTAR does not permit the installation of meters on its
poles, except for cable TV amplifiers. Specific approval
shall be obtained by NSTAR for such installations and shall
conform to Massachusetts Electrical Code requirements.
(Refer to Article 907)
Installation On Pedestal
For residential and small commercial applications only, the
installation of the meter socket shall be permitted to be
mounted on a free-standing pedestal pending the approval
of the authority having jurisdiction. The customer may be
required to provide protective devices for and at the freestanding
pedestal. (See Sketch 14)
B. Indoor Meters
Multiple meter bank-installed indoors shall be mounted so
that the center of the top meter(s) is no more than
6 feet and the center of the bottom meter is no less than 3
feet above the floor level. A clear area of 3 feet is required
in front of each meter.
705. Location of Service Disconnect and Current
Limiting Protection
A. Hot Sequence
In general, the service disconnect shall be located on the
load side of the meter (hot sequence metering).The
service disconnecting means shall be installed at a readily
accessible location nearest the point of entrance of the
service entrance conductors. (See Sketch 15)
B. Cold Sequence
The service disconnect shall be located on the line side of
the individual meter socket (cold sequence metering) for
the following applications:
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79

ARTICLE 706
80
1. On all ampere services on 480 volt 3 wire and
277/480 volt 4 wire installations.
2. For all instrument transformer installations, each set of
transformers installed must be cold sequenced and have
its own service disconnect switch except in the case of
padmount metering. (Refer to Article 720)
The disconnect switch in all applications must be in close
proximity and within sight to each meter socket. Contact
NSTAR and the local inspection authority for specific
installation requirements.
C. Current Limiting Protection
Current limiting protection shall be installed on the line
side of any new or upgraded meter socket for the
following application:
1. On all distribution underground network services both
for residential and commercial applications.
2. In other specific instances where the available fault
current exceeds 10,000 amperes.
3. Cold sequence may also be required when applying
current limiting protection.
706. Meter Mounting
Meter sockets and meter-breaker centers shall be mounted
plumb and firmly secured to supports. Where supports are
attached to masonry or concrete walls, expansion bolts or
anchors shall be used. Wood plugs driven into holes in
masonry, concrete, plaster, or similar materials are not
acceptable.
Wooden meter boards shall be constructed of 3/4 inch PT40
plywood or equal.
ARTICLE 707-708
707. Clearance
Ample workspace shall be provided around meters to allow for
testing, reading, and repairing. (See Sketch 13)
A clear working space of 3 feet is required in all directions
around the front of all meters and/or metering cabinets and
equipment per the Massachusetts Electrical Code.
All gas meters and associated equipment or propane cylinders
must be a minimum of 3 feet from the electrical service and
metering equipment.
708. Identification of Meter Sockets and Customer
Disconnecting Means for Multiple Meter Installations
For installations consisting of more than one meter, all meter
sockets and customer disconnecting means shall be plainly and
permanently marked both internally and externally for proper
suite, floor, office, etc., by the electrical contractor or owner.
Service will not be provided to a building that has unidentified
meter sockets. Contact the NSTAR New Customer Connect
Tech Center concerning information on meter socket markings.
In apartment and office buildings viewed from the approach to
the front entrance, mark each meter position LEFT or RIGHT,
FRONT or REAR, FLOOR NUMBER, and NUMBER of
apartment, office or suite.
Note:
The above markings and NSTAR’s M-13 form shall be
completed by the electrical contractor and verified by a
representative of NSTAR. Contact the NSTAR New Customer
Connect Tech Center or go to www.nstar.com for a copy of the
M-13 form.
Service shall not be instituted until the above requirements have
been completed.
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ARTICLE 709-711
709. Moving or Removing Metering Equipment
Meters, instrument transformers, and other metering devices
are the property of NSTAR. Relocation, removal or alteration
for wiring or connection purposes must be performed by an
authorized employee of NSTAR; except when specific permission
is obtained from NSTAR.Violators will be prosecuted.
When an existing service is “upgraded,” it is the responsibility
of the electrician to ensure that removed meters and accessory
equipment are accessible for return to NSTAR. If metering
equipment is lost or destroyed, NSTAR reserves the right to
seek restitution for all equipment.
710. Meter Connections
The service or line side conductors are always connected to
the top terminals of meter sockets or banks and the load side
conductors to the bottom terminals. A number of typical
connections for socket meter installations are shown in
Sketches 16 through 21. These diagrams show the actual
positions of the jaws for the socket meters.
711. Security
No electrical contractor, electrician, or property owners shall
by-pass a meter socket or install jumpers in a meter socket
without first securing permission from the Meter Operations
Department via the NSTAR New Customer Connect Tech
Center. The contractor shall install a transparent
polycarbonate cover and ring on the socket for the purpose of
safety. NSTAR will install the proper metering once an
application for service, a deposit (where required), and an
inspection by the local inspection authority are all received.
At the time permission is requested, the electrical contractor
shall supply the following information to the NSTAR New
Customer Connect Tech Center:
ARTICLE 711
A. Customer’s name and address
B. Meter number
C. Nature of work
D. Electrician’s name, telephone number, and license number
When performing a service upgrade from a 2 wire to 3 wire,
service, it will be the electrical contractor’s responsibility to see
that the meter is returned undamaged to NSTAR.
An estimated bill for unmetered use will be rendered by NSTAR
based on available data for the number of days the service is
unmetered. Electrical contractors or other persons found bypassing
services or using jumpers without prior permission will
be held responsible for any expenses incurred by NSTAR, and
may be subject to any other redress available to NSTAR.
A. For Single Phase 3 wire, services
Due to the use of an automated meter reading system, meters
cannot be reinstalled by the electrical contractor without first
contacting the NSTAR New Customer Connect Tech Center.
B. Meter Seals
Authority to cut meter seals or other sealing devices is
restricted to authorized NSTAR employees. It is the
responsibility of the electrical contractor to call the NSTAR
New Customer Connect Tech Center and request meter
removal or the cutting of any meter seal or other sealing
device.
Authority may be delegated to other than authorized NSTAR
employees, but only by specific request for a specific
installation. It is the responsibility of the electrical contractor
to call the NSTAR New Customer Connect Tech Center, and
request permission before removing or cutting any meter seal
or other sealing device of NSTAR.
82 83

ARTICLE 712-715
712. Meter Accessories
A. Telephone Line for Interval Data Metering
Applications
For interval data meter installations NSTAR may require an
analog voice grade dedicated telephone line alongside the
meter, terminated with a RJ-11 jack. The customer shall
contact the NSTAR New Customer Connect Tech Center for
determination of your applicable rate and application as to
whether an interval data meter will be installed.
B. Optional Enhanced Metering Service
For metering, pulse output, remote access metering and
interval data metering requests, refer to the applicable
optional enhanced metering rate service tariff.
METER SOCKETS
715. Meter Sockets for Self-Contained Meters
Approved sockets for self-contained meters must be listed for the
use by a recognized testing agency. See section A of this article
for more specific details. To insure the accurate registration of
energy usage, the meter socket must be of the proper type that
matches the installed service from NSTAR’s distribution
system.
84
A. Sockets with Manual Bypass
All non-residential and common area meter applications
shall have sockets with manual bypasses. Bypasses are
required to permit a meter change without customer service
interruption with the following requirements:
1. Horn and automatic bypasses are not permitted.
2. NSTAR approved single-handle, manually operated,
LOCKING jaw manual lever by-pass (commercial grade)
with safety arc shields are required on all services. For
services 100 amperes or less a non-locking manual lever
by-pass is acceptable.
ARTICLE 715
3. After the meter is installed and the bypass handle is in the
down position (not in bypass position), the mechanism
must be visible in the open position with the cover off.
4. It must not be possible to replace the meter socket cover
when the handle is in the bypass position.
5. A manual bypass is not to be used as a service disconnect.
B. 200 Amperes or Less
Self-contained socket metering is standard practice on single
phase and three phase installations where the service
capacity is not greater than 200 amperes and the voltage is
not greater than 480 volts.
All 480 volt, 3 wire and 4 wire sockets shall be equipped
with acceptable safety arc shields. A disconnect is required
ahead of and in close proximity to each meter socket and
shall be within sight of the meter socket (cold sequence). If
the disconnect switch is not visible at the meter location
then it must be a lockable device.
The following is a list of socket type metering requirements for
services rated 200 amperes or less:
1. Single phase, 3 wire, 120/240 volt service: A 4 terminal
meter socket is acceptable, except for residential services
in Boston (Downtown/network area), Cambridge,
Charlestown, a 5th terminal. (See Sketches 17 and 18)
2. Single phase, 3 wire, 120/208 volt service: A 5
terminal meter socket is required. (See Sketches 17
and 18)
85

ARTICLE 715
86
3. Three phase, 3 wire delta, 240 and 480 volt service:
A 5 terminal meter socket with manual bypass is
required. (See Sketch 19)
4. Three phase, 4 wire wye, 120/208 and 277/480 volt
service: A 7 terminal meter socket with manual bypass
is required. (See Sketch 20)
C. 400 Amperes or Less (320 Amperes Continuous
Load Capacity)
In general, self-contained socket metering (class 320) is
standard practice on single phase and three phase
installations where the service capacity is greater than
200 amperes and less than or equal to 400 amperes and the
voltage is not greater than 480 volts.
All class 320 meter installations shall be pre-approved by
the local inspection authority prior to starting work.
All approved class 320 meter sockets must be listed for use
by a recognized testing agency and have a single lever type
manually operated bypass, locking jaws, and safety shield.
All 480 volt, 3 wire and 4 wire services shall be equipped
with a disconnect switch ahead of each meter socket and
shall be within sight of the meter socket (cold sequence). If
the disconnect switch is not visible at the meter location
then it must be a lockable device.
The following is a list of socket meter requirements for
class 320 meter sockets:
1. Single phase, 3 wire, 120/240 or 120/208 volts:
A 5 terminal (in the 6 o’clock position) meter socket
with manual bypass is required. (See Sketch 21)
2. Three phase, 4 wire wye, 120/208 or 277/480 volts:
A 7 terminal meter socket with manual bypass is
required. (See Sketch 22)
ARTICLE 716-720
D. Sockets for 200 Amperes or Less Residential or
Commercial Underground Services
All 200 amperes or less 120/240 or 120/208 voltage
residential or commercial underground services shall be
ringless type with lugs on the left side of the meter socket
and bus bar connections to the line side of the meter jaws:
Residential Milbank CAT#U1980-0 or equivalent cooper
B-line CAT#EN20L44GRST or equivalent Siemans/Landis
& Gyr CAT#SUAS877-PG or equivalent.
Commercial-MILBANK CAT #U3924-XL or equivalent.
Any conduit attaching to this meter socket should have
expansion joints.
716. Cover Plates
In those instances where the meter cannot be immediately
installed upon completion of the wiring in the meter socket,
the customer is responsible to have a rigid plastic transparent
cover with blades installed in the meter socket. This cover
shall prevent accidental contact with any energized parts of the
socket as well as providing physical protection until the meter
can be installed. Under no circumstances shall cardboard be
substituted for the above described cover.
INSTRUMENT TRANSFORMER INSTALLATION
720. Instrument Transformers and Enclosures
It is the responsibility of the customer to contact the NSTAR
New Customer Connect Tech Center or the NSTAR web site
(www.nstar.com) for the proper dimensions and mounting
provisions for each set of metering current transformers.
The customer will furnish and install:
A. Current transformer cabinet with the following:
87

ARTICLE 720
1. Double hinged doors.
2. A locking hasp for a padlock type seal.
3. Transformer mounting facility (Lee Products CT-800,
Anchor 730 CP or equivalent).
4. For three wire installations, single phase or three
phase, a bus bar shall be installed on the common
phase or neutral, equipped with a 1/4 inch, 20
threaded screw for NSTAR metering only.
5. For four wire installations, a neutral block shall be
installed on the bottom of the current transformer
compartment for NSTAR metering only.
(See Sketch 23)
B. NSTAR transformer rated meter socket cabinet, which
must have the NSTAR approved label. See Sketch 24 for
location. NSTAR approved transformer rated meter
sockets vendor part numbers (which are subject to change,
refer to www.nstar.com for most current) are:
• Single Phase Form 4S 6 Terminal Meters
Milbank Cat#UC4964-O-WC-21-NST
Meter Devices Cat#602-U3060A-6-717
• Three Phase, 3 Wire Form 5S 8 Terminal Meters
Milbank Cat#UC4965-0-WC-21-NST
Meter Devices Cat#602-U3060A-8-716
Landis & Gyr Siemens Cat #9837-0905
• Three Phase, 4 Wire Form 9S 13 Terminal Meters
Milbank Cat#UC4966-0-WC-21-NST
Meter Devices Cat#602-U3060A-13-587
Landis & Gyr Siemens Cat#9837-0906
C. A 1 1/2 inch EMT, rigid metal conduit, schedule 40
conduit, or nipple with pull string shall be provided
ARTICLE 721-722
between the transformer cabinet and the meter test switch
cabinet/enclosure for the instrument transformer
secondaries.
The secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum, and
shall not exceed 75 feet.
NSTAR will furnish and install:
A. Meter and transformer secondary wiring from the current
and potential transformers to the meter test switch.
B. Current transformers and if potential transformers are
required.
Each set of current transformers and potential transformers
installed must be cold sequence and have its own service
disconnect switch except in the case of pad mount metering.
Line side bus cables must be clearly phase identified.
For additional information please contact the NSTAR New
Customer Connect Tech Center.
721. Use of Instrument Transformer Cabinets
Except for NSTAR-owned metering equipment, no
instruments, meters or other equipment shall be placed in the
transformer compartments or connected to the secondaries of
metering transformers. Instrument transformers or their
compartments shall not be used as junction boxes or junction
points to supply other loads.
Where voltage transformers are required and the service
voltage does not exceed 600 volts, they may be installed in the
current transformer compartment.
88
89

ARTICLE 722
722. Pad-Mount Metering
Where a new single customer is supplied from a pad-mounted
transformer, NSTAR Meter Operations Department will
consider locating the instrument transformers on the padmounted
distribution transformer. For location of meter
socket and cabinet/enclosure, see Sketch 24.
The customer will furnish and install:
A. Transformer rated meter socket cabinet, which must have
the NSTAR approved label. See Sketch 24 for location.
NSTAR approved transformer rated meter sockets vendor
part numbers (which are subject to change, refer to
www.nstar.com for most current) are:
• Single Phase Form 4S 6 Terminal Meters
Milbank Cat#UC4964-O-WC-21-NST
Meter Devices Cat#602-U3060A-6-717
• Three Phase, 3 Wire Form 5S 8 Terminal Meters
Milbank Cat#UC4965-0-WC-21-NST
Meter Devices Cat#602-U3060A-8-716
Landis & Gyr Siemens Cat #9837-0905
• Three Phase, 4Wire Form 9S 13Terminal Meters
Milbank Cat#UC4966-0-WC-21-NST
Meter Devices Cat#602-U3060A-13-587
Landis &Gyr Siemens Cat#9837-0906
B. A 1 1/2-inch EMT, rigid metal conduit, schedule 40
conduit, or nipple with pull string shall be provided
between the transformer cabinet and the meter test switch
cabinet/enclosure for the instrument transformer secondaries.
The secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum, and
shall not exceed 75 feet.
ARTICLE 723-730
NSTAR will furnish and install meter and transformer
secondary wiring from the current and potential transformers
to the meter test switch.
723. Primary Metering
Specifications and requirements for the delivery of and
acceptance of service at the available primary voltage,
including provisions for primary metering, will be furnished
upon request. Please contact the NSTAR New Customer
Connect Tech Center.
METAL ENCLOSED BUS DUCT SWITCHGEAR 600
VOLTS OR LESS
730. General
Please contact the NSTAR New Customer Connect Tech
Center for proper dimensions and mounting provisions for
metering current transformers for specific applications.
Approved switchgear and other service equipment must have
the following provisions:
A. A barrier that physically isolates the instrument
transformers from all other equipment. (See Sketches 25
and 26)
B. A separate door for the instrument transformer
compartment with padlocking facilities.
C. Each set of current transformers installed must be cold
sequence and have its own service disconnect.
D. NSTAR will require mounting space for metering and
auxiliary equipment. Refer to section 704 and 720. The
secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum
and not exceed 75 feet. A minimum 30 x 30 x 3/4 inch,
90 91

ARTICLE 740-802
92
pressure treated or equal, plywood meter board is
required for exclusive use by NSTAR.
E. Except for NSTAR owned equipment, no instruments,
meters or other equipment shall be placed in the
instrument transformer compartments or connected to
the secondaries of the instrument transformers.
METAL ENCLOSED SWITCHGEAR OVER 600 VOLTS
740. General
Please call the NSTAR New Customer Connect Tech Center
for specific requirements for your installation.
ARTICLE 800 UTILIZATION EQUIPMENT
801. General
Electric service must not be used in such manner as to cause
unusual fluctuations or disturbances in NSTAR’s distribution
system. In the case of a violation of this rule, NSTAR may
discontinue service or require the customer to modify the
installation with approved controlling devices. Motor and
other installations connected to NSTAR’s lines must be of a
type to use minimum starting current and must conform to
the requirements of NSTAR and the applicable electrical code
with respect to wiring, kind of equipment and control devices.
802. Nameplate Data
All motors must have manufacturer’s nameplate specifying all
information required by Article 430 of the Massachusetts
Electrical Code.
A. Definitions & Notes:
1. The terms “starting current” and “locked rotor current”
are synonymous.
2. Total locked rotor current is defined as the steady state
ARTICLE 802
current taken from the supply line with motor rotor(s)
locked, with all other power consuming components,
including a current reducing starter, if used, connected
in the starting position and with rated voltage and
frequency applied.
3. Where equipment contains more than one motor and
some motors are arranged for coincident starting, the
starting current is determined by the particular
combination of motors simultaneously started that
produces a higher starting current than any other
combination. For sequential starting, the interval between
successive steps shall not be less than 1/2 second.
4. The starting current for AC motors shall be in the order
of four to six times the normal operating current. Even
this condition may result in excessive voltage
fluctuations and light flicker, which may be objectionable
to the customer, as well as other customers supplied
from the same lines. For this reason, the customer shall
connect and start his motorized equipment so as not to
exceed a 3 percent voltage drop in service voltage upon
motor start as measured at the point of service entrance.
5. Maximum allowable starting current for motors up to
and including 20 horsepower or 225,000 Btu/hr is
tabulated on the next pages. These limits are based on
not more than four starts per hour with long periods of
continuous operation at maximum load.
6. Before purchasing and installing any motor equipment,
the customer shall contact the NSTAR New Customer
Connect Tech Center to verify the nominal utilization
voltages, frequency and phase characteristics of the
service to be supplied, the capacity available and the
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ARTICLE 802
suitability of the proposed equipment for operation at the
intended location. Attempting to operate a motor at other
than its nameplate characteristics will result in
unsatisfactory performance and, in certain instances, could
cause injury to personnel and/or damage to equipment.
B. Limitation of Motor Size
NSTAR reserves the right to refuse service to the following:
1. Single phase motors larger than 5 hp. Single phase motors
of larger rating may be permitted, provided NSTAR’s
facilities are adequate to supply the service and provided
the use of such motor or motors does not interfere with
the quality of service rendered to other customers.
2. Polyphase motors larger than 5 hp operated from a single
phase service by use of a phase converter.
3. Motor installations aggregating less than 7 hp would
typically be a single phase installation. Specific permission
from NSTAR will be required in all cases involving
polyphase motors of less than 7 hp.
4. NSTAR further reserves the right to limit the size of the
largest motor, which may be operated on any part of the
system.
C. Single Phase Motors
1. 120 Volt Supply – Motors with rating of 1/2 hp or less and
window-type air conditioning units whose running load
current does not exceed 7 amperes, with not more than
forty starts per hour and with a locked rotor current not
exceeding 50 amperes, may be connected to 120 volt supply.
Motors having a full load running current of more than 7
amperes but less than 12 amperes, and conforming to the
above locked rotor current limitations, may be connected
94
ARTICLE 802
to a 120 volt branch circuit only if such branch circuit
supplies the one unit and does not supply lighting units
or other appliances. It is strongly recommended that
units drawing more than 7 amperes full-load running
current be connected to 240 or 208 volt circuits.
2. 208 or 240 Volt Supply – Motors with ratings larger than
1/2 hp but less than 5 hp will be regularly supplied at
208 or 240 volts, provided the locked rotor current does
not exceed the values given in Table No.1. In
predominantly residential areas, and for small
commercial installations, the NSTAR New Customer
Connect Tech Center should be contacted before
installing motors with ratings over 2 hp.
3. Maximum Locked Rotor Currents – Single phase motors
supplied from combined light and power secondary
systems shall not have locked rotor current values in
excess of those shown in Table No. 1. Motors having
locked rotor current values in excess of those shown in
the table shall be equipped with starters, which will limit
the current to the values specified. Domestic laundry
equipment, with operating cycles and electrical
characteristics as currently available, is considered
acceptable.
Motors that start more than four times per hour are an
exception to the above and may cause interference to
other customers. Automatically and frequently started
motors for general use, such as motors for refrigerators,
oil burners, and similar devices shall not have a locked
rotor current exceeding 23 amperes at 120 volts or 29
amperes at 240 volts. For multi-motored devices
arranged for starting of motors one at a time, the locked
rotor current limits shall apply to the individual motors.
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ARTICLE 802
4. Single Phase Motors on Three Phase Service – Where
single phase motors are supplied from a three phase
service, they shall be properly balanced across the three
phases.
D. Three Phase Motors
1. Size of Motors – In order that the proper capacity may
be available to supply the load, the NSTAR New
Customer Connect Tech Center shall be advised of all
motors to be installed.
2. Maximum Locked Rotor Currents – Three phase
motors supplied from combined light and power
secondary systems shall not have locked rotor current
values in excess of those shown in Table No. 2. Starting
compensators are ordinarily required for three phase
motors 7 hp and larger. Exceptions to this practice will
be allowed to the extent that local distribution facilities
will permit. Motors having current values in excess of
those shown in the Table No. 2 shall be equipped with
starters that will limit the current to the values
specified. Increment start motors must have not less
than a one-half second interval between steps.
E. Supply Voltage - Special
230 Volt and 230/208 Volt Motors Operated from a 208
Volt Supply:
A nominal supply voltage of 208 volts can vary by 5%.
Motors rated 230 volts and 230/208 volts will not operate
satisfactorily at the lower limits of this range. For this
reason, motors purchased for use on a 208 volt supply
should be rated 208 volts.
TABLE 1
Single Phase Motors
ARTICLE 802
Maximum Locked Rotor Current Values in Amperes
This table is based on not more than four starts per hour with
long periods of continuous operation under maximum load
conditions. Contact the NSTAR New Customer Connect Tech
Center where these conditions cannot be met, or where
equipment rating and/or starting characteristics exceed the
following:
A. Equipment with motors rated in horsepower
Rated at
Maximum locked rotor current
115 volt 50 amps
230 volts, single 60 amps
phase 2 hp or less
2.5 to 5 hp Residential use
Contact the NSTAR Tech Center
Commercial use –60 amps plus 20 amps
per hp in excess of 2 hp
B. Air Conditioning or Heat Pump Equipment rated in
btu per Hour
Rated at
Maximum locked rotor current
230 volts, single phase 60 amps
20,000 btu/h or less
21,000 – 30,000 btu/h 60 amps plus 3 amps per 1,000 btu/h
in excess of 20,000 btu/h
Over 30,000 btu/h
Contact the NSTAR Tech Center
96 97

ARTICLE 802
TABLE 2
Three Phase Motors
Maximum Locked Rotor Current Values in Amperes
This table is based on not more than four starts per hour with
long periods of continuous operation under maximum load
conditions. Contact the NSTAR New Customer Connect Tech
Center where these conditions cannot be met, or where
equipment rating and/or starting characteristics exceed the
following:
A. Equipment with motors rated in horsepower
Rated at
Maximum locked rotor current
208* volts, three phase, 57.5 amps
2 hp or less
2.5 to 19.9 hp 57.5 amps per hp in excess of 2 hp
Over 19.9 hp
Contact the NSTAR Tech Center
B. Air Conditioning or Heat Pump Equipment rated in
btu per hour
Rated at
Maximum locked rotor current
208* volts, three phase, 57.5 amps
20,000 btu/h or less
21,000 – 50,000 btu/h 57.5 amps plus 1.15 amps per
1,000 btu/h in excess of 20,000 btu/h
51,000 – 225,000 btu/h 144 amps plus 1.15 amps per
1,000 btu/h in excess of 50,000 btu/h
Over 225,000 btu/h
Contact the NSTAR Tech Center
ARTICLE 803
803. Motor Protection
A. Protective Devices General
NSTAR strongly recommends that all motor installations
be adequately protected to prevent improper operation,
equipment damage and personal injury which might result
from abnormal conditions occurring in NSTAR’s service
facilities or the customer’s wiring system.
B. Protection Against Single Phase Operation
Three phase motors shall be protected against the
possibility of loss of any phase of the supply circuit.
NSTAR does not provide protection against loss of phase
conditions.
C. Undervoltage Protection
All motors requiring protection against the application of
full voltage at starting, or motors that would endanger life
and/or property by restarting after a service interruption
and a return to normal voltage shall be provided with
undervoltage protection. Such protection devices should
ensure that, with either undervoltage or no voltage, the
motor will be disconnected from the line or the starter
will be returned to the “off ” position.
NSTAR recommends the use of time-delay undervoltage
protection since instantaneous undervoltage protection
may operate on momentary voltage fluctuations.
D. Overload Protection
All motors shall be protected against overload by the
installation of adequate overcurrent thermal protective
devices or their equivalent, which operate to prevent
excessive motor winding temperatures.
* For 480 volts multiply current by 0.435
98
99

ARTICLE 804
E. Protection Against Phase Reversal
Control apparatus equipped with reverse phase relays shall be
installed by the customer on all polyphase motor installations
for elevators, hoists, cranes and those manufacturing
processes where accidental reversal of rotation is liable to
cause injury to persons and damage to machinery, equipment
or work in process.
The operation of this relay and associated circuit breaker shall
be instantaneous and shall be such that the circuit cannot be
re-energized until the normal phase relations are restored.
F. Installation of Undervoltage and Reverse Phase
Protective Device
Undervoltage relays and reverse phase devices, when
required, shall be installed by the customer on the load side
of meters.
G. Protection of Synchronous Motors
Information relative to the protection of synchronous motors
shall be obtained from the NSTAR New Customer Connect
Tech Center.
H. Damage to Equipment
NSTAR will not be responsible for damage caused to
customer-owned equipment where such damage is caused by
absence or failure of any of the above protective devices.
804. Fluctuating Loads
Welders, X-Ray equipment, motors connected to variable load
machinery, and other equipment having fluctuating load
characteristics may, for satisfactory service, require special
facilities. NSTAR reserves the right to withhold connection to
such loads, which are considered detrimental to the service of
other customers. The NSTAR New Customer Connect Tech
Center will advise the customer in these applications.
100
ARTICLE 901
A. Arc Welders
NSTAR reserves the right to refuse the supply or service to
any AC arc welder, which could cause interference or
disturb the quality of service to other customers.
Customers may be charged for any additions to the electric
distribution system required for continued operation of this
equipment.
B. Resistance Welding Machines
Shall not be installed on NSTAR’s lines without first
obtaining NSTAR’s permission. Customers may be charged
for any additions to the electric distribution system
required for continued operation of this equipment.
C. Intermittently Operated Equipment
Electric furnaces and boilers, heat pumps, X-ray
equipment, compressors, pumps, molding machines, or
similar equipment with load fluctuation at a frequency
greater than four times per hour should not be installed
except under conditions specified by NSTAR.
ARTICLE 900 RADIO, TELEVISION, CATV CARRIER
INSTALLATIONS
901. Operation
Service for the operation of radio and television transmitting
apparatus will be furnished under conditions specified by
NSTAR. Please contact the NSTAR New Customer Connect
Tech Center for additional information. Conditions of use of
such service shall not cause disturbance to the power supply of
other customers or handicap NSTAR in maintaining proper
system conditions. NSTAR delivers a 60 hertz sinusoidal wave
form subject to transients and other impurities consistent with
normal service. The customer is responsible for protecting his
equipment and devices from any adverse effects caused by these
conditions.
101

ARTICLE 902-906 ARTICLE 907-909
902. Installation of Eliminator or Trap
Where necessary, suitable eliminators or traps shall be installed
by the customer in such a manner as to prevent radio,
telephone and television interference feeding back into the
supply circuit.
903. Service Quality Requirements
Where service is required for a transmitting station or other
high frequency equipment at specific locations, it is essential
that the NSTAR New Customer Connect Tech Center be
contacted during early planning. Detailed technical
investigation will be necessary before giving assurance of
service to meet exacting requirements.
904. Attachments to Poles Prohibited
The attachment of antennae systems to poles carrying NSTAR’s
conductors is strictly prohibited due to the possibility of
serious results from accidental contacts. Such attachments will
be removed immediately upon discovery by NSTAR at
customer expense.
905. Clearance from NSTAR Conductors
Outdoor antennae, counterpoise and lead-in conductors shall
not cross over, but may cross under electric power circuits
provided that the requirements of both the Massachusetts
General Laws Chapter 166, Sections 21A through 21G and the
National Electrical Safety Code are met. These facilities shall
be kept away from all such circuits so as to avoid the possibility
of accidental contact by a falling antenna or lead-in wires.
906. Carrier Equipment
If a customer’s wiring is used for carrying current of a carrier
system for remote control of power, communication, or
signaling purposes, there must be installed suitable filter
equipment approved by NSTAR to keep NSTAR’s distribution
system free of any high frequency component produced by the
customer’s equipment.
907. Community Antenna Television (CATV) Systems
Community Antenna Television (CATV) Systems’ requests to
install coaxial cable or poles for the distribution of high
frequency signals employed in CATV systems shall be referred
to NSTAR. Request for power supply to a CATV power pack
or booster shall be referred to the NSTAR New Customer
Connect Tech Center. All construction shall conform to the
requirements of Massachusetts General Laws, Chapter 166A,
Community Antenna Television Systems NSTAR Standards,The
Massachusetts Electrical Code, Article 820, and any other
regulations for CATV pole line attachments.
908. Cellular Telephone Towers
Providers of cellular telephone service will be required to
contact the NSTAR New Customer Connect Tech Center
before the installation of any facilities.
909. Town Owned Street Lights
Some of the communities that NSTAR serves have purchased
the street lights and associated equipment from NSTAR. In
communities where this sale has occurred, the town or any
third party contractor of the town is responsible for the
operation and maintenance of the street lights and associated
equipment. NSTAR’s only obligation is to make or break the
connection to its distribution system. Please contact your
NSTAR Account Executive if there are any questions
concerning town owned street lighting.
102
103

APPENDIX A - SKETCHES INDEX
1. Standby Generator Installation Schematic Connection Diagrams
2. Typical Overhead Service Entrance Facilities
3. Minimum Vertical Service Clearance Above Ground and
Buildings
4. Service Mast Construction at Low Buildings – 400 Amperes or
Less Single Phase Maximum
5. Overhead Service Installation of Service Bolt
6A. Typical Residential Underground Service from Overhead
Facilities on Same Side of Street
6B. Typical Residential Underground Service from Overhead
Facilities on Opposite Side of Street
7. Typical Installation of Underground Service to a Single Building
400 Amperes or Less Fed From Overhead to Underground
Only
8. Typical Installation of Underground Service To A Single Building
400 Amperes Or Less Fed From A Manhole System
9. 800-1000 Ampere Special Terminal Box
10. Required Clearances Around NSTAR Owned Facilities
11. Padmounted Transformer Protection From Vehicular Traffic
12. Temporary Service Structure for Service 200 Amperes or Less
13. Minimum Clearances For All Self-Contained Meter Socket
Installations
14. Residential or Small Commercial Meter Pedestal Installation For
120/240 Volt, 400 Amperes or Less Service
15. Hot and Cold Sequence Diagrams
104
APPENDIX A - SKETCHES INDEX
16. NSTAR Meter Socket/Connection Requirements
17. Meter Installation for 200 Amperes, Single Socket, Single
Phase, 3 Wire, 120/240 or 120/208 Volt Service With 4 or 5
Terminal Meter Socket
18. Meter Installation for 200 Amperes, Multiple Sockets, Single
Phase, 3 Wire, 120/240 or 120/208 Volt Services With 4 or 5
Terminal Meter Sockets
19. Meter Installation for 200 Amperes,Three Phase, 3 Wire, 240
or 480 Volt Service With 5 Terminal Meter Socket and Bypass
20. Meter Installation for 200 Amperes,Three Phase, 4 Wire,
120/208 or 277/480 Volt Service With 7 Terminal Meter
Socket and Bypass
21. Meter Installation for 400 Amperes, Single Phase, 3 Wire,
120/240 or 120/208 Volts With 5 Terminal Meter Socket and
Bypass
22. Meter Installation for 400 Amperes, 3 Phase, 4 Wire, 120/208 or
277/480 Volt Service With 7 Terminal Meter Socket and Bypass
23. Typical Meter Installation Involving Current Transformers One
or More Cable Per Phase Each Cable No Larger Than 500 KCMIL
24. Transformer Rated Meter Installations With Meter Cabinet
Located Outdoors
25. Mounting Provisions and Dimensions For Metering Current
Transformers In Service Cubicles Rated 600 Volts,
1800 Amperes or Less
26. Mounting Provisions and Dimensions For Metering Current
Transformers In Service Cubicles Rated 600 Volts, 2000 –
6000 Amperes
105

SKETCH 1
SKETCH 2
Standby Generator Installation Schematic Connection Diagrams
Typical overhead Service Entrance Facilities
SERVICE DROP FURNISHED,
INSTALLED, OWNED AND
MAINTAINED BY NSTAR
APPROVED
WEATHERHEAD
ENTIRE LOAD TRANSFERABLE
ALLOW SUFFICIENT
CONDUCTOR (3 FEET)
TO FORM DRIP LOOPS.
From Meter and
Service Equipment
Sealable, Non-Fused
Double Throw Switch
Distribution
Transferable
Load
12 FT MINIMUM
WITH A MAXIMUM
OF 25 FEET
ALL FACILITIES, EXCEPT METER,
BEYOND THE POINT OF CONNECTION
IS FURNISHED, INSTALLED, OWNED
AND MAINTAINED BY THE CUSTOMER
CODE APPROVED CONDUCTORs IN CONDUIT
OR SERVICE ENTRANCE CABLE
Standby
Generator
OUTDOOR METER
SOCKET
6' Max
3' Min
BEARING
PLATE
PARTIAL LOAD TRANSFERABLE
To Meter
and Service
Equipment
Distribution
Distribution
SERVICE CABLE ATTACHMENT
FURNISHED, INSTALLED, OWNED
AND MAINTAINED BY CUSTOMER
106
Non-Transferable
Load
Sealable, Non-Fused
Double Throw Switch
Standby
Generator
Transferable
Load
1. Service Cable Attachment - See detail on Sketch 5
2. NSTAR Stock Code 508 - Service Bracket with flat mounting surface
Edison #4, without spool insulator. Bracket shall accommodate class
53-2 Spool Insulator.
3. NSTAR Stock Code 798 - Spool Insulator Class 53-2, approximate
size shall be 3 1/8 inch diameter by 3 inches high. Preferred color is
blue-gray.
4. Service attachment to be installed, not to cause service wire damage
against structures and violate Massachusetts electrical safety
codes/rules. 107

SKETCH 3
SKETCH 4
Minimum Vertical Service Clearance Above Ground and Buildings
Service Mast Construction of Low Buildings – Single Phase
FIGURE "A"
NOTE #4
NOTE#2
UNACCEPTABLE
NOTE#8
12'
12'
SPACES
ACCESSIBLE
TO PEDESTRIAN
ONLY
12'
OVER
SW.
18'
OVER
STREET
16'
DRIVEWAYS
16'
NOTE #5
18"
NOTE #3
8' (includes
drip loop) over
highest point of
roofs, balconies
or railings readily
accessible to
pedestrians and
3' from windows,
fire escapes or
similar locations
3' EXTENSION OF SERVICE
ADAPTER
ENTRANCE CABLE
BARE NEUTRAL
4" MIN.
A. Galvanized steel clamp
and standard bracket
furnished, installed, owned
and maintaine by customer
Or 3'-0" MAX.
B. UNGUYED
Approved insulators
1'-0" MIN. }
and clamps supplied with
mast kit. (All furnished,
installed, owned and
maintained by customer)
3'-0"
MAX.
WEATHERHEAD
1. These clearances apply to service of 300 volts to ground or less having cabled
conductor with ground neutral.
2. This distance may be reduced to 10 feet if voltage is 150 volts or less to ground
and no telephone or CATV service is present. The maximum height is 25 feet
and must be accessible from a ladder positioned on a secure flat surface.
3. Vertical distance may be reduced to 3.5 feet if roof or projections are not
readily accessible to pedestrian traffic.
4. Service connection located above building extension as represented in Figure
“A” is not acceptable because the service connection cannot be reached from a
ladder placed on the ground.
5. Where the voltage between conductors does not exceed 300 volts, a
reduction in clearance over the roof to not less than 18 inches shall be
permitted if, (1) the conductors do not pass over more than 4 feet of the
overhead portion of the roof and (2) the conductors are terminated at a
through-the-roof raceway or approved support.
6. The clearances above equal or exceed the requirements of the Massachusetts
Electrical Safety Code and ANSI C2.
7. Locations of all services, new and rebuilt, must be approved by NSTAR.
8. Where the voltage exceeds 300 volts to ground but is less then 600 volts to
ground, the clearances shall change to 15 feet.
108
FLAT OR
SLANTED
ROOF
MAST MADE OF 2"
GALVANIZED RIGID STEEL
CONDUIT MINIMUM. DO NOT
USE ALUMINUM CONDUIT.
TO METER
SEE NOTE #5
1. Mast fastenings to building & mast guys shall be designed for 1,000
LBS minimum force applied at service cable attachment.
2. The service drop span shall not exceed 100 feet.
3. The customer must assume the responsibility for the ability of the
installation to support the service drop.
4. Service structures for road crossings must be of sufficient height to
maintain an 18 feet minimum road clearance. If the service drop does
not cross a street, or driveway clearance may be reduced to 12 feet.
5. Clearance of 15 feet preferred, 12 feet minimum above ground.
109

SKETCH 5
SKETCH 5 (NOTES)
Overhead Service Installation of Service Bolt
FRAME
BUILDING
VENEER
SIDING
5/8" x 8" MACHINE BOLT
5/8" x 12" MACHINE BOLT
BOLT HEAD
COUNTERSUNK
AT LEAST
3"
2"
BOLT HEAD
COUNTERSUNK
AT LEAST
3"
2"
CHECK
NUT
CHECK
NUT
BLOCK FASTENED SECURELY
TO STUDDING
STUDDING
BOARDING
SHINGLES OR
OTHER FINISH
STANDARD NUT & WASHER
SPOOL AND CLEVIS
BLOCK FASTENED SECURELY
TO STUDDING
BOARDING
STUDDING
VENEER SIDING
STANDARD NUT & WASHER
SPOOL AND CLEVIS
1. Bolts to be furnished and installed by customer in location to be
specified by the company.
2. Bolts & nuts to be hot dipped galvanized, to have machine thread & to
project 2 inches beyond outer face of building, except where
otherwise specified.
3. Bolt may be put through studding or other suitable timber provided
the location is correct for the service connection.
4. Service attachment to be installed, not to cause service wire damage
against structures and violate Massachusetts electrical safety
codes/rules.
TOP VIEW
AT LEAST
4"
STUDDING
LATHS
WASHER
BRICK
BUILDING
FURRING
5/8" x 12"
MACHINE BOLT
STANDARD NUT & WASHER
SPOOL AND CLEVIS
THIS NUT TO BE SET UP TIGHT
AGAINST WALL TO PREVENT BOLT
BACKING UP OR TURNING
2 1/2"
AT LEAST
3"
110
111

SKETCH 6A
SKETCH 6A (NOTES)
Typical Residential Underground Service from
Overhead Facilities on Same Side of Street
1. Local wiring authorities may have additional requirements to those
shown here.
10'
NSTAR OR JOINTLY OWNED POLE
CONTRACTOR SHALL LEAVE A 20' LONG
(UNCUT)COIL OF CABLE FOR NSTAR TO
LATER CONNECT TO OVERHEAD SUPPLY
RISER PIPE AND CONDUIT TO
HAND-HOLE SEE NOTES
Meter by NSTAR
ONE LOOP OF CABLE IN HAND-HOLE
OR USE SUBMERSIBLE-TYPE CONNECTOR
U.G. SERVICE INSTALLED PER MASS. ELECT. CODE
6 FEET MAX
3 FEET MIN
2. If Customer’s cable from the hand hole to the meter is direct buried, it
should be slack in trench to allow for settling and frost. For sidewalk
crossing section, unless there are stricter requirements by state or local
ordinances, use minimum 3 inch diameter schedule 80 PVC from the
handhole to the riser backfilled with clean sand and red “ELECTRIC”
marker tape above it.
3. Riser pipe, sweep and conduit to hand-hole shall be minimum 3 inches
steel (R.M.C.) or schedule 80 PVC conduit, R.M.C. requires a
grounding connector for connection to #4 CU wire.
SERVICE
PANEL
4. Weather seal riser pipe opening around cables with duct sealing
compound (UL R13335).
POLE GROUND WIRE
& CONNECTION BY NSTAR
SEE NOTE 2
5. The service conduit exiting the hand-hole towards the meter requires a
watertight seal around the cables. As required by Massachusetts
Electric Code. Use product like 3M Co. Scotchcast #2135.
MUNICIPAL
PROPERTY
ELEVATION
PRIVATE PROPERTY
ALL WORK IN THE PUBLIC WAY
WILL BE PERFORMED BY NSTAR
6. If an NSTAR representative requires an oversized riser cable section to
accommodate potential future loading, NSTAR will supply those
materials at no charge.
POLE
CUSTOMER SHALL FURNISH AND INSTALL ENTIRE
SERVICE EXCEPT FOR THE METER (BY NSTAR)
ALTERNATE METER (PEDESTAL) LOCATION
SIDEWALK
CUSTOMER OWNS & MAINTAINS THIS PORTION
NSTAR OWNS & MAINTAINS THIS PORTION, INCLUDING HAND-HOLE
112
113

SKETCH 6B
SKETCH 6B (NOTES)
Typical Residential Underground Service from
Overhead Facilities on Opposite Side of Street
1. Local wiring authorities may have additional requirements to those
shown here.
10'
NSTAR OR JOINTLY OWNED POLE
CONTRACTOR SHALL LEAVE A 20' LONG
(UNCUT)COIL OF CABLE FOR NSTAR TO
LATER CONNECT TO OVERHEAD SUPPLY
RISER PIPE AND CONDUIT TO
HAND-HOLE SEE NOTES
Meter by NSTAR
U.G. SERVICE INSTALLED PER MASS. ELECT. CODE
ONE LOOP OF CABLE IN HAND-HOLE
OR USE SUBMERSIBLE-TYPE CONNECTOR
6 FEET MAX
3 FEET MIN
2. If Customer’s cable from the hand-hole to the meter is direct buried,
it should be slack in trench to allow for settling and frost. For
roadway crossing section, unless there are stricter requirements by
state or local ordinances, use minimum 3 inch diameter schedule 80
PVC from the handhole to the riser backfilled with clean sand and
red “ELECTRIC” marker tape above it.
3. Riser pipe, sweep and conduit to hand-hole shall be minimum 3
inches steel (R.M.C.) or schedule. 80 PVC conduit, R.M.C. requires
a grounding connector for connection to #4 CU wire.
POLE GROUND WIRE
& CONNECTION BY NSTAR
ELEVATION
SERVICE
PANEL
SEE NOTE 2
4. Weather seal riser pipe opening around cables with duct sealing
compound (UL R13335).
5. The service conduit exiting the hand-hole towards the meter requires
a watertight seal around the cables. As required by Massachusetts
Electric Code. Use product like 3M Co. Scotchcast #2135.
POLE
MUNICIPAL
PROPERTY
STREET
PRIVATE PROPERTY
ALL WORK IN THE PUBLIC WAY WILL BE
PERFORMED BY NSTAR
CUSTOMER SHALL FURNISH AND INSTALL ENTIRE
SERVICE EXCEPT FOR THE METER (BY NSTAR)
ALTERNATE METER (PEDESTAL) LOCATION
6. If an NSTAR representative requires an oversized riser cable section
to accommodate potential future loading, NSTAR will supply those
materials at no charge.
CUSTOMER OWNS & MAINTAINS THIS PORTION
NSTAR OWNS & MAINTAINS THIS PORTION, INCLUDING HAND-HOLE
114
115

SKETCH 7
Typical Installation of Underground Service to a Single Building 400
Amperes or Less Fed from Overhead to Underground Only
SKETCH 8
Typical Installation of Underground Service to a Single Building 400
Amperes or Less Fed from a Manhole System
METER
CUSTOMER'S METER
SOCKET
METER
CUSTOMER'S METER
SOCKET
6'-0" MAX
3'-0" MIN
TERMINAL
BOX
6'-0" MAX
3'-0" MIN
TERMINAL
BOX
GROUND LEVEL
GROUND LEVEL
CABLE IN
CONDUIT
CUSTOMER'S
QUARTERBEND
CABLE IN
CONDUIT
CUSTOMER'S
QUARTERBEND
1. A clear area of 3 feet is required in front of the meter.
2. If a service disconnect is being installed, it is subject to the following:
A.Installation is subject to the authority having jurisdiction.
B. It shall be installed on the line side of the meter.
C.The bottom of the disconnect switch shall be physically mounted no
lower than 3 feet from the finished grade.
3. The bottom of the meter shall be no lower than 3 feet from the
finished grade.
116
1. A clear area of 3 feet is required in front of the meter.
2. If a terminal box is being installed, it is subject to the following:
A. Sized in accordance with the Massachusetts Electrical Code.
B. The bottom of the terminal box shall be physically mounted no
lower than 3 feet from the finished grade.
3. If a service disconnect is being installed, it is subject to the following:
A. Installation is subject to the authority having jurisdiction.
B. It shall be installed on the line side of the meter.
C. The bottom of the disconnect switch shall be physically mounted
no lower than 3 feet from the finished grade.
4.The bottom of the meter shall be no lower than 3 feet from the
finished grade.
117

SKETCH 9
SKETCH 10
800-1000 Ampere Special Terminal Box
Required Clearances Around NSTAR Owned Facilities
NSTAR Facilities include:
TERMINAL LUGS
(SEE BELOW)
ALL TERMINAL BOXES SHALL
HAVE 1/4" DRAIN HOLES
THROUGH BOTTOM OF
TERMINAL BOX
TERMINAL LUGS
SERVICE ENTRANCE CABLES
#14 GUAGE GALVANIZED STEEL (MIN)
APPROVED NON-COMBUSTIBLE
INSULATING SUPPORT,
CENTER MOUNTED IN BOX
FLAT BAR COPPER BUS CONDUCTOR OF
PROPER CURRENT CAPACITY
SPECIAL TERMINAL BOX TO
BE SIZED PER THE MA ELECTRICAL CODE
WITH A MINIMUM SIZE OF 48"X48"X20"
TO CUSTOMER
1.Transformer/foundations,
splice/junction boxes,
manholes, switch gear/
foundations and,
handholes/pedestals.
2. Shaded clearance area
surrounding nstar
facilities shall be clear of
all plantings,
uncontrolled growth,and
the installation of
unauthorized structures.
This is to ensure that
NSTAR will have the
necessary clearance to
operate and maintain
their equipment.
4 FEET MIN.
(NOTE 3)
EDGE OF ROAD
4
FEET
2-4
INCHES
ELECTRICAL
FACILITY*
(NOTE 1)
EDGE OF PAVEMENT
PLAN VIEW
TELCO
CATV
LAYOUT
SHADED AREA TO BE CLEAR OF ALL
LANDSCAPING & ALL
METERING EQUIPMENT
SEE NOTE 2
4
FEET
1"
3" 1 1 /4"
1 1 /2"
3"
CUSTOMER TO
DRILL HOLES 7 /16" AND FURNISH 3 /8" -16 REQUIRED
LENGTH BOLTS EACH WITH WASHER AND NUT.
ALL SILICON BRONZE OR EQUIVALENT. THE COMPANY
WILL CONNECT SERVICE ENTRANCE CABLES ONLY,
USING CUSTOMER-SUPPLIED LUGS.
3. Meter pedestals for
temporary or permanent
services shall not be
installed within a
minimum of 4 feet of a
transformer pad.
4. Handholes installed in
paved surfaces shall be
even, but not below,
finished grade.
4
FEET
1/2 IN.
ELEVATION
TYPICAL
TRANSFORMER
(NOTE 4)
4
FEET
ELEVATION
TYPICAL HANDHOLE
118
119

SKETCH 11
Padmounted Transformer Protection From Vehicular Traffic
SKETCH 12
Temporary Service Structure for Service 200 Amperes or Less
Service Structure 3' Min. in Ground
Approved Weatherhead
Service Drop Cable
(Max. Span 100')
4
APPROX.
4' TO TOP
OF BRACE
See
Note 2
4
4
Service Entrance
Cable
All Wood
Braces 2"x4"
Meter
10' MIN
NSTAR Electric shall:
A. Make service drop
cable connection to
its distribution system
1' Max.
B. Furnish, install, and
maintain the meter
APPROX.
5'
Ground
Conductor
APPROX.
5'
Buried Ground
Rod
All Stakes
(Wood)
2"x4"x3'
1. The above specified clear area distances to buildings or landscaping
shall be maintained to: inspect, provide access, perform switching and
ventilate the transformer.
2. If no curb exists, or transformer is located closer than 10 feet to the
traveled way, protective vehicle posts shall be installed on exposed side
as specified.
3. Vehicle posts shall be 4 inches galvanized steel pipe minimum, filled
with concrete and extend 42 inches above and below grade. Larger
diameter posts may be required for some installation.
4. Contact NSTAR to ensure transformer meets the minimum distances
to doors windows, fire escapes, air intakes and walls.
120
1. 6 inches X 6 inches timber shall extend into ground a minimum of
3 feet.
2. Service structures for road crossings must be of sufficient height to
maintain an 18 feet minimum road clearance. If drop does not cross
street, clearance may be reduced to 12 feet.
3. All timbers to be sound and free of knots.
4. Minimum of 4-10d nails or larger at each joint.
5. Grounding conductor shall be stapled to timber at frequent intervals.
6. Equivalent structure may be used with the approval of NSTAR.
7. Approved manual bypass required.
121

SKETCH 13
Minimum Clearances For All Self-Contained Meter Socket Installations
SKETCH 14
Residential or Small Commercial Meter Pedestal Installation For
120/240 Volt, 400 Amperes or Less Service
1" MINIMUM
OVERHANG
OF PLYWOOD
AROUND
TROUGH
EXPANSION
JOINTS REQUIRED
3'
HORIZONTAL SOCKETS
OR BANKS INDOORS
1. A clear working space area of 3 feet is required in all directions around
the front of all meters, and/or metering cabinets and equipment as
required by Massachusetts Electrical Code to allow reading, testing,
and repairing or replacing of such equipment.
2. All gas meters and associated equipment must be a minimum of 3 feet
from the electrical service and metering equipment.
3. The 8 inch horizontal clearance must be maintained from an adjacent
wall or from any equipment mounted on the wall.
4. Vertical & horizontal clearances between meters must be maintained
when sockets are installed.
5. Taps to 5th terminal to be installed by contractor with a #12 solid
copper or #10 solid aluminum AWG conductor depending on service
conductor, insulated in a white jacket.
122
1. The entire pedestal including meter socket and service conductors furnished are
owned and maintained by the customer.
2. A clear work area of three feet is required in all directions of the meter pedestal.
3. All terminal boxes to be sized per the Massachusetts Electrical Code
(if applicable).
4. Pedestal must maintain a minimum clearance of 4 feet from utility poles, and
transformers.
5. The 3/4 inch pressure treated or equal plywood panel board shall be sized to
accommodate the meter socket, a terminal box and service disconnect device
(if applicable).
6. A service disconnect may be required in accordance with Massachusetts Electric
Code. If a service disconnect is being installed, it is subject to the following:
a. Installation is subject to the authority having jurisdiction.
b. It shall be installed on the line side of the meter.
c. The bottom of the disconnect switch shall be physically mounted no lower
than three feet from the finished grade.
7. Installation of pedestal subject to the approval of the authority having
jurisdiction.
123

SKETCH 15 SKETCH 16
Hot and Cold Sequence Diagrams
Company Meter Socket and Connection Requirements
Service Number Location of
Size Service Number Socket of Sketch Serv.Disconnect
(Amps) (Volts) of Phases Wires Terminals Number (Hot or Cold Seq.)
200 120/240 1 3 4 17,18 H
HOT SEQUENCE METERING
LINE
M
METER
COMPARTMENT
SERVICE
DISCONNECT
SWITCH
LOAD
200 120/208 1 3 5 17,18 H
200 240 3 3 5 19 H
200 480 3 3 5 19 C
200 120/208 3 4 7 20 H
200 277/480 3 4 7 20 C
400 120/240 1 3 5 21 H
400 120/208 1 3 5 21 H
400 120/208 3 4 7 22 H
COLD SEQUENCE METERING
LINE
METER
DISCONNECT
SWITCH
M
LOAD
METER
COMPARTMENT
400 277/480 3 4 7 22 C
1. All sockets must be listed for use by a recognized testing agency.
2. For more specific details regarding location of service disconnect (hot or
cold sequence) refer to section 705.
3. For locations where current limiting protection is required refer to
section 705C.
4. For specifics regarding sockets with manual bypass refer to section 715.
124 125

SKETCH 17
Meter Installation for 200 Amperes, Single Socket, Single Phase, 3 Wire,
120/240 or 120/208 Volt Service With 4 or 5 Terminal Meter Socket
SKETCH 18
Meter Installation for 200 Amperes, Multiple Sockets, Single Phase, 3 Wire,
120/240 or 120/208 Volt Service With 4 or 5 Terminal Meter Socket
HORIZONTAL
VERTICAL
SERVICE
NEUTRAL
LINE
LINE
LOAD
LOAD
5TH TERMINAL
LINE
LOAD
1.There must be neutral terminals at each meter location. Taps to the
fifth terminal to be installed by the contractor with a #12 solid
copper or #10 solid aluminum AWG conductor depending on service
conductor, insulated in a white jacket.
2. Drain hole in the bottom of meter socket must be punched out.
3. Refer to article 715 for by-pass requirements.
4. For network installation a 5th terminal – 9 o’clock position with the
exception of residential gang installation. 5th terminal may be located
at the 6 o’clock position.
5. Commercial/Industrial installations – 5th terminal shall be located at
either the 9 or 6 o’clock position with a manual bypass.
LINE
SERVICE
NEUTRAL
LOAD #1
3 WIRE
Refer to Sketch 17 Notes.
LOAD #2
3 WIRE
GANG INSTALLATION
LOAD #3
3 WIRE
126
127

SKETCH 19
Meter Installation for 200 Amperes, Three Phase, 3 Wire, 240 or
480 Volt Service With 5 Terminal Meter Socket and Bypass
SKETCH 20
Meter Installation for 200 Amperes, Three phase, 4 Wire, 120/208 or
277/480 Volt Service With 7 Terminal Meter Socket and Bypass
LINE
LINE
NA B C
COMMON PHASE
CONNECTION
SERVICE
NEUTRAL
5th
TERMINAL
BY-PASS
LEVER IN
BY-PASSING
POSITION
SERVICE
NEUTRAL
BONDED TO
BOX
BY-PASS
LEVER IN
BY-PASSING
POSITION
LOAD
N
A B C
LOAD
1. COMMON PHASE CONNECTION MUST BE INSULATED
FROM THE SOCKET.
On Three Phase Delta only A & C phases are bypassed; B phase is
always energized and 5th terminal permanently attached at 6 o’clock
position.
2. Drain hole in the bottom of meter socket must be punched out.
3. A manual, single handled bar with locking jaw bypass and safety arc
shield is required.
4. 5th Terminal located at 6 o’clock.
128
1. Drain hole in the bottom of meter socket must be punched out.
2. A manual, single handled bar with locking jaw by-pass and safety arc
shield is required.
129

SKETCH 21
Meter Installation for 400 Amperes, Single phase, 3 Wire, 120/240
or 120/208 Volts With 5 Terminal Meter Socket and Bypass
LINE
SKETCH 22
Meter Installation for 400 Amperes, 3 Phase, 4 Wire, 120/208 or
277/480 Volt Service With 7 Terminal Meter Socket and Bypass
LINE
N A B C
LINE
BY-PASS
LEVER in
by-passing
position
5th
TERMINAL
7th
TERMINAL
NEUTRAL BAR
Service
neutral
bonded
to box
NEUTRAL
BAR
LOAD
N A B C
1. Meter socket must have a single handle lever operated bypass, locking
jaws and flash shield.
2. Drain hole in the bottom of the meter socket must be punched out.
3. 5th terminal to be located at the 6 o’clock position.
4.Taps to 5th terminal to be installed by contractor with a #12 solid
copper or #10 solid aluminum AWG conductor depending on service
conductor, insulated in a white jacket.
Refer to Sketch 21 Notes
130
131

SKETCH 23
Typical Meter Installation Involving Current Transformers One or
More Cable Per Phase Each Cable No Larger Than 500 KCMIL
SKETCH 24
Transformer Rated Meter Installations With Meter Cabinet Located Outdoors
METER SOCKET
LOCATED OUTSIDE
METER
METER
NOTE 2
1 1/2" CONDUIT
METER
SOCKET
SERVICE
SWITCH
OR
BREAKER
LINE
NEUTRAL BAR
A
D
B
CABLE
CONNECTORS
LOAD
C - DEPTH
SLIP METER RISER
FOR PVC APPLICATION
NOTE 3
FINISHED GRADE
6' - 0"
5' - 4"
NOTE 4
1. See article 720 for more specific details on the requirements of the
meter cabinet and associated equipment.
TO NSTAR PADMOUNT XFMR
SECONDARY SIDE
2 FOOT IN CONCRETE
1. All locations and installations are subject to NSTAR approval.
2. Customer to supply and install NSTAR approved transformer rated
meter socket. See article 720 for more specific details on the
requirements of the meter cabinet and associated equipment.
3. 4 foot channel iron 3/8 inch, painted.
4. 1 1/2 inch EMT or PVC conduit with pull string.
5.The location of the meter cabinet shall be a minimum of 3 feet but not
to exceed 75 feet from the padmounted transformer or switchgear.
6. A clear area of 3 feet is required in front of meter socket.
132
133

SKETCH 25
Mounting Provisions and Dimensions For Metering Current Transformers
In Service Cubicles Rated 600 Volts, 1800 Amperes or Less
MIN. MIN. MIN. MIN.
4 1"
8 1" 8 1" 4 1"
2 2 2 2
CLEARANCE TO
NEAREST OBJECT
FIGURE 1 FIGURE 2
BUS SPACING
SIDE VIEW
IN CUBICLE
OF CUBICLE
1 1"
2
1"
1"
5 7"
8
SEE FIG. 3 & 4
7"MIN.
7"MIN.
1/4"-20 TAPPED HOLES
ON LINE SIDE ONLY,
AND ON NEUTRAL BUS
11"
2
1 1"
1"
2
1
2
ALL MOUNTING HOLES 9/16" DIA.
ACCESS DOOR
OF CUBICLE
7"
APPROX.
MIN.
7"
8 1"
2
INSULATED BUS
SUPPORTS
1 3"
4
10"
1 3"
4
ALL MOUNTING HOLES 9/16" DIA.
FIGURE 3 FIGURE 4
225A-1200A
(1400A TO
SWITCH OR C/B
1800A SWITCH
(WITH 1200A
OR C/B)
FRAME MAX.)
7"
8
SKETCH 25 (NOTES)
1. It is the responsibility of the customer to contact the Company for
proper dimensions and mounting provisions for each set of metering
current transformers.
2. Current transformers are to be supplied and mounted by NSTAR
on the bus, on the load side of the service circuit breaker or switch.
3. Current transformers are to be mounted on the face of the bus
toward the access door of the cubicle. If multiple busses are used,
spacers will be furnished & installed by the manufacturer.
4. No physical supports other than the primary terminals are required
for the current transformers.
5. The access door to the current transformer compartment must be
hinged and have a locking hasp for a padlock type seal.
6. Figure 1 shows a 4 wire-3Ø installation. On 3 wire – 3Ø & 3 wire –
1Ø installations, transformers are to be mounted on outside busses
only & filler bus for the common phase or neutral will be furnished &
installed by the manufacturer.
7. The manufacturer will furnish and install hex head machine bolts 1/2
inch – 13 thread, nuts, washers for current transformer mounting,
and 1/4 inch – 20 potential screws.
8. The cubicle should be located in the switch room where there is a
minimum clearance of 3 feet from the door of the cubicle to a wall
or other obstruction.
9. Meters are to be located on the outside of the building. A 1-1/2 inch
conduit for the secondary wiring will be required from the current
transformer location to the meter location. This conduit is not to
exceed 25 feet unless written permission has been obtained. A pull
string is required for wiring installation.
10.Line side bus must be clearly identified.
134
135

SKETCH 26
Mounting Provisions and Dimensions For Metering Current Transformers
In Service Cubicles Rated 600 Volts, 2000 - 6000 Amperes
6"
MIN.
10"
MIN.
10"
MIN.
6"
MIN.
1/4"-20 TAPPED HOLES ON LINE SIDE ONLY,
AND ON NEUTRAL BUS
1 1"
2
1 1"
2
7"MIN.
8 1"
2
MIN.
7"MIN.
8 1"
2
1 3"
4
10"
1 3"
4
ACCESS
DOOR OF
CUBICLE
INSULATED
TRANSFORMER
SUPPORTS
CLEARANCE TO
NEAREST OBJECT
9" 7"
APPROX.
MIN.
INSULATED
BUS
SUPPORTS
BUS & SPACING ALL 1"
4
FIGURE 1 FIGURE 2
ACCESS VIEW OF CUBICLE
SIDE VIEW OF CUBICLE
7"
8
SKETCH 26 (NOTES)
1. It is the responsibility of the customer to contact the Company for
proper dimensions and mounting provisions for each set of metering
current transformers.
2. Current transformers will be supplied & mounted by NSTAR.
Window type current transformers are to be mounted in the bus on
the load side of the service circuit breaker or switch.
3. The manufacturer will furnish and install filler bus, hex head bolts,
1/2 inch – 13 thread, nuts & washers for filler bus mounting, 1/4
inch – 20 potential screws, and 3 inch wide insulated transformer
supports.
4. Physical supports are required for the window type current
transformers.
5. The access door to the current transformer compartment must be
hinged & have a locking hasp for a padlock type seal.
6. Figure 1 shows a 4 wire - 3Ø installation. On 3 wire - 3Ø & 1Ø
installations, transformers are to be mounted on the outside busses
only.
7. The cubicle should be so located in the switch room that there is a
minimum clearance of 3 feet from the door of the cubicle to a wall or
other obstruction.
8. Meters are to be located the outside of the building. A 1-1/2 inch
conduit for the secondary wiring will be required from the current
transformer location to the meter location. This conduit is not to
exceed 25 feet unless written permission has been obtained. A pull
string is required for wiring installation.
9. Line side bus must be clearly identified.
ALL MOUNTING HOLES 9/16" DIAM.
FIGURE 3
2000A, 3000A, 4000A, CURRENT TRANSFORMERS
(2000A TO 6000A SWITCH OR C/B)
136
137

APPENDIX B GENERAL LAWS APPENDIX B GENERAL LAWS
APPLICABLE GENERAL LAWS
INTENTIONAL INJURY TO ELECTRIC METER OR
OTHER PROPERTY
M.G.L. Chapter 164, Section 127
Whoever unlawfully and with intent to avoid payment by himself or
another person for a prospective or previously rendered service the
charge or compensation for which is measured by a meter or other
mechanical device injures or destroys, or suffers to be injured or
destroyed, any meter, pipe, conduit, wire, line, pole, lamp or other
apparatus belonging to a corporation engaged in the manufacture or
sale of electricity or to any person or whoever unlawfully and with
intent to avoid payment by himself or another person for a
prospective or previously rendered service prevents an electric
meter from duly registering the quantity of electricity supplied, or
in any way interferes with its proper action or just registration, or
without the consent of such corporation or person, unlawfully and
intentionally diverts or suffers to be diverted any electrical current
from any wire of such corporation or person, or otherwise
unlawfully and intentionally uses or causes to be used, without the
consent of such corporation or person, any electricity
manufactured or distributed by such corporation, or charged to
such person, shall be punished by a fine of not more than one
thousand dollars or by imprisonment for not more than one year,
or both.
The existence of any of the conditions with reference to meters or
attachments described in this section shall be prima facie evidence
that a firm, corporation or other business entity, commercial or
industrial, to whom such electricity is, at the time, being furnished
by or through such meters or attachments has, with intent to
defraud, created or caused to be created with reference to such
meters or attachments, the condition so existing; provided,
138
however, that nothing in this paragraph shall be construed to limit
the introduction of any other competent evidence bearing upon the
question of whether or not the defendant was responsible for the
acts alleged to have been committed; provided, further, that the
prima facie evidence referred to in this paragraph shall not apply to
a residential customer; provided, further, that the prima facie
evidence referred to in this paragraph shall not apply to any firm,
corporation or other business entity, commercial or industrial, so
furnished with electricity for less than thirty-one days or until
there has been at least one meter reading, whichever first occurs.
THEFT OF ELECTRICITY; TRIPLE DAMAGES
M.G.L. Chapter 164, Section 127A
Whoever unlawfully and intentionally injures or destroys, or
suffers to be injured or destroyed, any meter, pipe, conduit, wire,
line, pole, lamp or other apparatus belonging to a corporation,
including municipal corporations which own municipal lighting
plants engaged in the manufacture or sale of electricity or gas or to
any person, or unlawfully and intentionally prevents an electric or
gas meter from duly registering the quantity of electricity or gas
supplied, or in any way interferes with its proper action or just
registration, or without the consent of such corporation or person,
unlawfully and intentionally diverts or suffers to be diverted any
electric current from any wire or gas from any pipe of such
corporation or person, or otherwise unlawfully and intentionally
uses or causes to be used, without the consent of such corporation
or person, any electricity or gas manufactured or distributed by
such corporation, or charged to such person shall be liable to such
corporation or person for triple the amount of damages sustained
thereby or one thousand dollars, whichever is greater. Damages
shall include the value of the electricity or gas used and the cost of
equipment repair and replacement. Any damages assessed under
139

GENERAL LAWS
GENERAL LAWS
the provisions of this section in excess of the actual damages
sustained by the corporation or person manufacturing, distributing
or selling such electricity or gas shall be paid to the
commonwealth; provided, however, that if a municipal lighting
plant brings an action pursuant to this section such damages in
excess of the actual damages shall be paid to such municipal
lighting plant.
COMING INTO CLOSE PROXIMITY TO HIGH
VOLTAGE LINES
M.G.L. Chapter 166, Section 21A
No person shall require or permit any employee to operate a
crane, power shovel or other such types of construction equipment
in close proximity to overhead high voltage lines; nor to enter
upon any land, building or other premises to engage in
construction work, including excavation, demolition, repair or
other such work or to erect, install, operate or store in or upon
such premises any machinery or construction equipment, including
well drilling, pile driving or hoisting equipment, where it is
intended to perform such work or operate such equipment in
close proximity to overhead high voltage lines unless and until
contact with said high voltage lines has been effectively guarded
against in the manner hereinafter prescribed. For the purposes of
this section and sections twenty-one B to twenty-one G the words
“in close proximity to overhead high voltage lines” shall mean
within six feet of such lines.
PROTECTION OF OVERHEAD HIGH VOLTAGE LINES
M.G.L. Chapter 166, Section 21B
The operation or erection of any tools, machinery or equipment,
or any part thereof capable of vertical lateral or swinging motion;
the handling or storage of any supplies, materials or apparatus or
the moving of any house or other building, or any part thereof,
under, over, by or near overhead high voltage lines shall be
prohibited, if at any time during such operation or other
manipulation it is intended or necessary to bring such equipment,
tools, materials, buildings or any part thereof within six feet of
such overhead high voltage lines, except where such high voltage
lines have been effectively guarded against danger from accidental
contact, by either:
1. The erection of mechanical barriers to prevent physical
contact with high voltage conductors; or
2. De-energizing the high voltage conductors and grounding
where necessary. Only in the case of either of such exceptions
may the six foot clearance required be reduced.The required
six foot clearance shall not be provided by movement of the
conductors through strains impressed by attachments or
otherwise upon the structures supporting the overhead high
voltage lines, nor upon any equipment, fixtures, or
attachments thereon.
If neither (1) or (2) are practicable in the opinion of the
utility company or other owner or (operator) of such
overhead lines, and it is necessary to temporarily relocate the
high voltage conductors, mutually agreeable arrangements
shall be made with the owner or operator of such lines for
their temporary relocation.
3. In addition to (1) and (2), an insulated cage type guard or
other effective protective device of a type approved by the
commissioner of labor and industries shall be installed about
the boom or arm of all hoisting or other such construction
equipment, except backhoes or dippers, being operated in
proximity of overhead high voltage lines.
4. All mechanical barriers and all insulated protective devices
referred to herein shall be of such character and construction
140 141

GENERAL LAWS
as are suited to work operations, and adequate for the
electrical conditions to be encountered.
5. All mechanical barriers and all insulated protective devices
shall be maintained in good functioning condition and shall be
subject to periodic inspection.
The provisions of this section and the preceding section,
insofar as they require the erection of mechanical barriers or
the de-energizing of high voltage conductors, shall not apply
to the transportation of a crane, power shovel or other similar
types of construction equipment upon a public way when
such equipment is being transported to a construction site.
WARNINGS; OPERATION OF EQUIPMENT NEAR
HIGH VOLTAGE LINES
M.G.L. Chapter 166, Section 21C
The owner, agent or employer responsible for the operation of
equipment shall post and maintain in plain view of the operator on
each crane, derrick, power shovel, drilling rig, hay loader, hay
stacker, pile driver, or similar apparatus, any part of which is
capable of vertical lateral or swinging motion, an approved
weather-resistant warning sign legible at twelve feet reading
“WARNING- Unlawful to operate this equipment within SIX FEET
of high voltage lines.”
WARNING SIGNS; SIZE; POSTING
M.G.L. Chapter 166, Section 21D
Warning signs shall be placed:
1. Within the equipment readily visible to operators of cranes
and other equipment when at the controls of such
equipment.
GENERAL LAWS
2. On the outside of equipment in such number and locations as
to be readily visible to mechanics or other persons engaged in
the work operations.
Warning Signs shall be not less than five inches in height, nor
less than seven inches in width.
NOTIFICATION OF OPERATION NEAR HIGH
VOLTAGE LINES
M.G.L. Chapter 166, Section 21E
Before any operations are to be performed within six feet of any
overhead high voltage lines, the person or persons responsible for
the work to be done shall promptly notify the utility or other
company owning or operating the overhead high voltage lines.
The work shall be performed only after satisfactory arrangements
have been negotiated between the owner or operator of the lines
and the contractor.
EXEMPTIONS; DEFINITIONS
M.G. L. Chapter 166, Section 21F
The provisions of sections twenty-one A to twenty-one E,
inclusive, shall not apply to the construction, reconstruction,
operation and maintenance of overhead electrical conductors and
their supporting structures and associated equipment by authorized
electrical workers; nor to any authorized person engaged in the
construction, reconstruction, operation and maintenance of
overhead electrical or communications circuits or conductors and
their supporting structures and associated equipment of rail
transportation systems, electrical generating, transmission or
distribution systems, or communications systems.
As used in section twenty-one A to twenty-one F, inclusive, the
words “high voltage” shall mean a voltage in excess of four
hundred and forty volts, measured between conductors, or
142 143

GENERAL LAWS
measured between the conductor and the ground; the words
“mechanical barrier” shall mean, temporary devices for separating
and preventing contact between material or equipment and
overhead electrical conductors, such as:
a. Series of poles or the equivalent;
b. Non-conductive enclosures around conductors.
“De-energizing” shall mean removing the voltage
from electrical conductors.
“Temporary relocation” shall mean:
a. Removing electrical conductors from poles;
b. Elevating electrical conductors from poles;
c. Rerouting electrical conductors.
“Authorized Person” shall mean:
a. Employees of a light and power company with respect
to the electrical system of such a company, and the
employees of a transportation system with respect to
the electrical circuits of such system;
b. Employees of communication utilities, state, county or
municipal agencies having authorized circuit
construction on the poles or structures of an electric
power company or transportation system or
communication system;
c. Employees of an industrial plant with respect to the
electrical system of such plant.
d. Employees of any electrical or communications
contractor with respect to work under his supervision.
GENERAL LAWS
“Warning Sign” shall mean a weather resistant sign of not
less than five inches by seven inches with a yellow background
and black lettering reading as follows: “WARNING –
Unlawful to operate this equipment within SIX FEET of high
voltage lines.”
VIOLATIONS; PENALTIES
M.G.L. Chapter 166, Section 21G
A. Whoever violates any of the provisions of sections twentyone
A to twenty-one F, inclusive, shall be punished by a fine
of not less than one hundred dollars, nor more than one
thousand dollars or by imprisonment for not more than one
year, or both.
B. If a violation of any of the provisions of sections twenty-one
A to twenty-one F, inclusive, results in physical or electrical
contact with any overhead high voltage line, the person, firm,
corporation or association violating said provisions shall be
liable to the owner or operator of such high voltage line for
all damage resulting from such contact and for all liability
incurred by such owner or operator as a result of any such
contact.
INTENTIONAL INJURY OR DESTRUCTION OF
PROPERTY; PENALTY
M.G.L. Chapter 166, Section 38
Whoever unlawfully and intentionally injures, molests or destroys
any line, wire, pole, pier or abutment, or any of the materials or
property of any street railway company, of any electric railroad
company, or of any city or town engaged in the manufacture and
sale of electricity for light, heat or power or of any company,
owner or association described in sections twenty-one and fortythree
shall be punished by a fine of not more than five hundred
144 145

GENERAL LAWS
dollars or by imprisonment for not more than two years, or both;
and whoever does any act prohibited by this section between the
hours of four o’clock in the afternoon and seven o’clock in the
forenoon shall be punished by a fine of not more than one thousand
dollars or by imprisonment for not more than four years, or both.
LARCENY; GENERAL PROVISIONS AND PENALTIES
M.G.L. Chapter 266: Section 30
Whoever steals, or with intent to defraud obtains by a false
pretence, or whoever unlawfully, and with intent to steal or
embezzle, converts, or secretes with intent to convert, the
property of another … whether such property is or is not in his
possession at the time of such conversion or secreting, shall be
guilty of larceny, and shall … if the value of the property stolen
exceeds two hundred and fifty dollars, be punished by
imprisonment in the state prison for not more than five years, or
by a fine of not more than twenty-five thousand dollars and
imprisonment in jail for not more than two years; or, if the value of
the property stolen … does not exceed two hundred and fifty
dollars, shall be punished by imprisonment in jail for not more than
one year or by a fine of not more than three hundred dollars.
PERSONAL PROPERTY; MALICIOUS OR WANTON
INJURIES
M.G.L. Chapter 266, Section 127
Whoever destroys or injures the personal property … of another
in any manner or by any means not particularly described or
mentioned in this chapter shall, if such destruction or injury is
willful and malicious, be punished by imprisonment in the state
prison for not more than ten years or by a fine of three thousand
dollars or three times the value of the property so destroyed or
injured, whichever is greater and imprisonment in jail for not more
GENERAL LAWS
than two and one-half years; or if such destruction or injury is
wanton, shall be punished by a fine of fifteen hundred dollars or
three times the value of the property so destroyed or injured,
whichever is greater, or by imprisonment for not more than two
and one-half years; if the value of the property so destroyed or
injured is not alleged to exceed two hundred and fifty dollars, the
punishment shall be by a fine of three times the value of the
damage or injury to such property or by imprisonment for not
more than two and one-half months; provided, however, that where
a fine is levied pursuant to the value of the property destroyed or
injured, the court shall, after conviction, conduct an evidentiary
hearing to ascertain the value of the property so destroyed or
injured.The words "personal property'', as used in this section,
shall also include electronically processed or stored data, either
tangible or intangible, and data while in transit.
“DIG SAFE” LAW; EXCAVATIONS, NOTICE, PENALTY
M.G.L. Chapter 82, Section 40 through Section 40E
Section 40.The following words, as used in this section and
sections 40A to 40E, inclusive, shall have the following
meanings:
Company, natural gas pipeline company, petroleum or
petroleum products pipeline company, public utility company,
cable television company, and municipal utility company or
department that supply gas, electricity, telephone,
communication or cable television services or private water
companies within the city or town where such excavation is to
be made.
“Description of excavation location”, such description
shall include the name of the city or town, street, way, or route
number where appropriate, the name of the streets at the
146 147

GENERAL LAWS
148
nearest intersection to the excavation, the number of the
buildings closest to the excavation or any other description,
including landmarks, utility pole numbers or other information
which will accurately define the location of the excavation.
“Emergency”, a condition in which the safety of the public is
in imminent danger, such as a threat to life or health or where
immediate correction is required to maintain or restore
essential public utility services.
“Excavation”, an operation for the purpose of movement or
removal of earth, rock or the materials in the ground
including, but not limited to, digging, blasting, augering,
backfilling, test boring, drilling, pile driving, grading, plowing
in, hammering, pulling in, jacking in, trenching, tunneling, and
demolition of structures, excluding excavation by tools
manipulated only by human power for gardening purposes and
use of blasting for quarrying purposes.
“Excavator”, any entity including, but not limited to, a
person, partnership, joint venture, trust, corporation,
association, public utility, company or state or local
government body which performs excavation operations.
“Premark”, to delineate the general scope of the excavation
or boring on the paved surface of the ground using white paint,
or stakes or other suitable white markings on nonpaved
surfaces. No premarking shall be acceptable if such marks can
reasonably interfere with traffic or pedestrian control or are
misleading to the general public. Premarking shall not be
required of any continuous excavation that is over 500 feet in
length.
“Safety zone”, a zone designated on the surface by the use of
standard color-coded markings that contains the width of the
facilities plus not more than 18 inches on each side.
GENERAL LAWS
“Standard color-coded markings”, red – electric power
lines, cables, conduit or light cables; yellow – gas, oil, street
petroleum, or other gaseous materials; orange –
communication cables or conduit, alarm or signal lines; blue –
water, irrigation and slurry lines; green – sewer and drain
lines; white – premark of proposed excavation.
“System”, the underground plant damage prevention system
as defined in section 76D of chapter 164.
Section 40A.
No excavator installing a new facility or an addition to an
existing facility or the relay or repair of an existing facility
shall, except in an emergency, make an excavation in any public
or private way, any company right-of-way or easement or any
public or privately owned land or way, unless at least 72 hours,
exclusive of Saturdays, Sundays and legal holidays but not more
than 30 days before the proposed excavation is to be made,
such excavator has premarked not more than 500 feet of the
proposed excavation and given an initial notice to the system.
Such initial notice shall set forth a description of the excavation
location in the manner as herein defined. In addition, such
initial notice shall indicate whether any such excavation will
involve blasting and, if so, the date and the location at which
such blasting is to occur.
The notice requirements shall be waived in an emergency as
defined herein; provided, however, that before such excavation
begins or during a life threatening emergency, notification shall
be given to the system and the initial point of boring or
excavation shall be premarked.The excavator shall ensure that
the underground facilities of the utilities in the area of such
excavation shall not be damaged or jeopardized.
149

GENERAL LAWS
In no event shall any excavation by blasting take place unless
notice thereof, either in the initial notice or a subsequent
notice accurately specifying the date and location of such
blasting shall have been given and received at least 72 hours in
advance, except in the case of an unanticipated obstruction
requiring blasting when such notice shall be not less than four
hours prior to such blasting. If any such notice cannot be given
as aforesaid because of an emergency requiring blasting, it shall
be given as soon as may be practicable but before any
explosives are discharged.
Section 40B.
Within 72 hours, exclusive of Saturdays, Sundays and legal
holidays, from the time the initial notice is received by the
system or at such time as the company and the excavator
agree, such company shall respond to the initial notice or
subsequent notice by designating the location of the
underground facilities within 15 feet in any direction of the
premarking so that the existing facilities are to be found within
a safety zone. Such safety zone shall be so designated by the use
of standard color-coded markings.The providing of such
designation by the company shall constitute prima facie
evidence of an exercise of reasonable precaution by the
company as required by this section; provided, however that in
the event that the excavator has given notice as aforesaid at a
location at which because of the length of excavation the
company cannot reasonably designate the entire location of its
facilities within such 72 hour period, then such excavator shall
identify for the company that portion of the excavation which
is to be first made and the company shall designate the location
of its facilities in such portion within 72 hours and shall
designate the location of its facilities in the remaining portion
GENERAL LAWS
of the location within a reasonable time thereafter.When an
emergency notification has been given to the system, the
company shall make every attempt to designate its facilities as
promptly as possible.
Section 40C.
After a company has designated the location of its facilities at
the location in accordance with section 40B, the excavator
shall be responsible for maintaining the designation markings
at such locations, unless such excavator requests remarking at
the location due to the obliteration, destruction or other
removal of such markings.The company shall then remark
such location within 24 hours following receipt of such
request.
When excavating in close proximity to the underground
facilities of any company when such facilities are to be
exposed, non-mechanical means shall be employed, as
necessary, to avoid damage in locating such facility and any
further excavation shall be performed employing reasonable
precautions to avoid damage to the underground facilities
including, but not limited to, any substantial weakening of
structural or lateral support of such facilities, penetrating or
destruction of any pipe, main, wire or conduit or the
productive coating thereof, or damage to any pipe, main, wire
or conduit.
If any damage to such pipe, main, wire or conduit or its
protective coating occurs, the company shall be notified
immediately by the excavator responsible for causing such
damage.
The making of an excavation without providing the notice
required by section 40A with respect to any proposed
150
151

GENERAL LAWS
GENERAL LAWS
excavation which results in any damage to a pipe, main, wire
or conduit, or its protective coating, shall be prima facie
evidence in any legal or administrative proceeding that such
damage was caused by the negligence of such person.
Section 40D.
Nothing in this section shall affect or impair local ordinances
or by-laws requiring a permit to be obtained before excavation
in the public way or on private property; but notwithstanding
any general or special law, ordinances or by law, to the extent
that any permit issued under the provisions of the state
building code or state fire code requires excavation by an
excavator on a public way or on private property, the permit
shall not be valid unless the excavator notifies the system as
required pursuant to sections 40 and 40A, before the
commencement of the excavation, and has complied with the
permitting requirements of chapter 82A.
Section 40E.
Any person or company found by the Department of Public
Utilities Telecommunications and Energy, after a hearing, to
have violated any provision of sections 40A to 40E, inclusive,
shall be fined $500 for the first offense and not less than
$1,000 nor more than $5,000 for any subsequent offense
within 12 consecutive months as set forth by the rules of said
department; provided, however, that nothing herein shall be
construed to require forfeiture of any penal sum by a state or
local government body for violation of section 40A or 40C;
and provided, further, that nothing herein shall be construed to
require the forfeiture of any penal sum by a residential
property owner for the failure to premark for an excavation of
such person’s residential property.
152 153